STUDENT’S  MANUAL. 


HASKELL. 


UNC 


The  Sheldon  Peck  Collection 
on  the  History  of  Orthodontics 
and  Dental  Medicine 


Gift  of 


Sheldon  Peck,  DDS  1966 

and 

Leena  Peck,  DMD 


Digitized  by  the  Internet  Archive 
in  2018  with  funding  from 
University  of  North  Carolina  at  Chapel  Hill 


https://archive.org/details/studentsmanualha00hask_0 


THE 


STUDENT’S  MANUAL 

AND 

HAND-BOOK 


FOR  THE 

DENTAL  LABORATORY. 


BY 

L.  P.  HASKELL, 

OF  THE  DENTAL  DEPARTMENT  OF  THE  NORTH-WESTERN  UNIVERSITY. 


PUBLISHED  BY 

WELCH  DENTAL  COMPANY, 

PHILADELPHIA. 

1887 


Copyright,  1887,  by  L.  P.  Haskell,  Chicago. 


PRESS  OF 

FRIENDS’  Printing 

SIXTH  AND  ARCH 


House, 

STS., 


PHILADELPHIA 


CONTEI^TS 


General  Principles, .  1 

Laboratory, .  2 

Tools  and  Appliances, .  4 

Blowpipe  —  its  Use,  .  6  ' 

Impressions, .  7 

Plaster  Casts, . 10 

Dies, . 14 

Swaging  Plates, . 17 

Fitting  Plates, . 21 

Clasps, . 22 

Investing,  Backing,  and  Soldering, . 24 

Finishing  Metal  Plates, . 27 

Preparation  of  Gold  and  Silver  Plate  and  the  making  .of 

Solders, . 28 

Attachment  of  Teeth  to  Plate, . 30 

Relative  Value  of  the  various  Materials  for  Plates,  ...  32 

Continuous-Gum  Work, . 35 

Furnaces, . 40 

Cast  Metal  Plates, . 42 

Vulcanized  Rubber, . 43 

Celluloid, . 47 

Gold  and  Silver, . 48 

Selection  and  Arrangement  of  Teeth, . 50 

Temperaments, . 55 

Temporary  Work, .  63 

Adjustment  in  the  Mouth, . 64 

Regulating  Teeth, . •  66 


PEEFACE. 


the  urgent  advice  of  members  of  the  profession, 
I  have  prepared  this  work,  for  which  there 
seems  to  be  a  place  in  the  laboratory  of  the  young 
dentist,  to  say  nothing  of  the  older  members  of  the 
profession,  who,  in  these  days  of  rubber  plates,  have 
had  little  experience  in  metal  work. 

The  text  books  are  too  diffusive,  embodying  too 
many  methods  for  the  same  object,  confusing  to  the 
student,  and  inconvenient  as  hand-books. 

This  hook  will  embody  the  result  of  forty  years’ 
experience  in  the  dental  laboratory  and  exclusive 
attention  to  prosthetic  dentistry,  furnishing  methods 
which  have  been  thoroughly  demonstrated  as  simple 
and  effective,  producing  satisfactory  results. 

It  is  not  intended  to  take  the  place  of  the  text-book 
in  the  dental  college,  though  the  student  will  find  it 
there  a  valuable  aid  in  the  prosecution  of  his  prepar¬ 
atory  work. 


CHAPTER  I. 


GENERAL  PRINCIPLES. 

T  N  examining  the  mouth  for  the  insertion  of  an 
f  artificial  denture,  there  should  be  taken  into 
account  all  its  conditions,  viz.:  the  shape  of  the  jaws, 
long  or  short,  deep  or  shallow,  hard  and  unyielding, 
soft  and  yielding  ;  a  solid  alveolar  ridge,  or  one  from 
which  the  bone  has  been  absorbed,  leaving  a  flexible 
condition ;  the  relative  position  of  the  j  aws,  whether 
the  lower  is  receding  or  protruding  ;  and  then  the 
remaining  teeth,  if  there  are  any;  for  often  a  few 
teeth  are  left,  sometimes  useful,  but  often  not  only 
useless,  but  interfering  with  the  comfort  and  useful¬ 
ness  of  the  artificial  denture.  If  the  patient  is  better 
off*  without  them,  advise  their  extraction. 

The  first  object  to  be  attained  is  comfort  and  use¬ 
fulness  ;  next,  artistic  appearance,  or  resemblance  to 
nature,  not  only  in  the  size,  shape,  color,  and  arrange¬ 
ment  of  the  teeth,  but  in  forming  the  artificial  gum, 
be  it  rubber  or  porcelain,  so  as  to  restore  the  contour 
of  the  lips. 

The  selection  of  material  for  plates,  the  patient 
should  leave  to  the  dentist,  presuming  he  has  been 
properly  educated  as  to  the  relative  value  of  each. 


2 


STUDENT^S  MANUAL 


Whatever  materials  and  methods  will  secure  the  best 
results  should  be  adopted. 

The  remark  is  often  made,  “  I  do  not  have  any  de¬ 
mand  for  metal  plates.”  That  is  true,  in  consequence 
of  the  universal  use  of  rubber,  consequently  you  must 
create  the  demand  by  showing  your  patients  the 
superiority  of  the  metal,  and  the  disadvantages  of  the 
rubber. 


CHAPTER  II. 


THE  LABORATORY. 

T  should  not  be  a  machine  shop,  but  adapted  to,  and 
arranged  for,  the  object  intended. 

It  should  be  large  enough  for  all  the  purposes  of  a 
dental  laboratory,  well  lighted,  and  easy  of  access 
from  the  operating  room. 

The  work-bench  should  be  in  front  of  the  window, 
as  it  is  difficult  to  work  advantageously  by  a  side  light. 
The  bench  should  be  of  hard  wood,  about  18  inches 
wide,  ll  inches  thick,  and  of  a  proper  height  to  sit 
down  and  work  at  easily. 


AND  HAND-BOOK. 


3 


The  gold  drawer  should  be  2  feet  long,  18  inches 
wide,  6  inches  deep,  with  the  front  cut  out  in  a  half 
circle,  so  as  not  to  be  in  the  way  in  filing.  In  it  should 
be  a  “gold-pan,”  14x10,  and  II  inches  deep,  with  a 
top  depressed  in  the  centre  and  perforated  with  small 
holes  for  the  filings  to  pass  through.  There  should  be 
a  hard-wood  knob  in  the  bench  over  the  drawer  to  file 
on.  If  there  is  plenty  of  room,  a  second  drawer,  with 
knob,  for  rubber-work,  is  desirable,  also  a  drawer  for 
refuse  wax,  and  over  which  to  “  wax-up.” 

The  piaster-bench  should  be  constructed  with  a  hole 
in  the  centre,  for  refuse  plaster  to  drop  through  into 
a  box  or  barrel ;  shelf  for  flasks,  and  a  tin  can  for 
plaster. 

The  molding-box  may  be  18  inches  square  and  4 
inches  deep,  placed  as  a  permanent  fixture,  with 
shelves  for  flasks,  dies,  etc. 

The  lathe  should  be  a  permanent  fixture  on  a  bench, 
with  good  light,  and  sufficiently  high  to  stand  at.  A 
machinist’s  lathe  is  not  adapted  for  dental  purposes, 
while  we  have  dental  lathes  admirable  in  all  their 
appointments.  Have  a  rack  for  the  appliances. 

The  tools  should  be  arranged  at  the  back  of  the 
bench,  within  easy  reach,  and  never  in  a  drawer. 
Have  in  the  rack  only  such  as  are  needed  for  dental 
purposes,  laying  duplicates  aside. 

A  movable  swaging-bloch,  to  be  kept  under  the 
bench,  by  the  side  of  gold-drawer,  is  made  as  follows : 


student’s  manual 


X=J 


8  inches  wide  at  the  top, 
and  11  inches  at  the  bot¬ 
tom,  just  high  enough  to 
pass  under  the  bench. 

Make  it  of  pine,  with  a 
plank  bottom,  to  which 
attach  heavy  castors,  a 
handle  on  one  side,  and  a 
pocket  for  the  hammer. 

Have  an  iron  six  -  inch 
cube  cast,  and  filling  the 
box  nearly  full  of  sawdust, 
place  the  cube  in  it  so  it 
will  extend  2  inches  above  the  box. 

If  you  intend  to  make  continuous-gum  work,  pro¬ 
vision  should  be  made  for  a  furnace. 


CHAPTER  HI. 


TOOLS  AND  APPLIANCES. 

(ENTAL  depots  are  filled  with  appliances,  many 
useless,  others  sometimes  useful  but  not  neces¬ 
sary.  The  following  are  indispensable  : 

FOR  METAL  WORK. 

Straight  Shears,  with  openings  Plate  Nippers, 
for  the  fingers.  Plate  Benders,  (lower.) 


AND  HAND-BOOK. 


5 


Plate  punch. 

Hammer,  for  swaging. 

Horn  or  wood  mallet. 

Files,  round,  and  half-round 
Small  vise  and  anvil. 

Slate,  for  borax. 

Sheet  iron  soldering  pan. 
Articulators. 

Lathe  appliances. 

Felts  and  brushes  for 
ing. 

Acid  dish,  lead. 

Sieve. 

Molding  flask,  5  in.  diameter, 
3  in.  deep,  of  iron. 

Gas-pipe  so  arranged  as  to  be 


Pliers,  round-nosed. 

Pliers,  flat-nosed. 

Hammer,  riveting. 

Plate  burnisher. 

Tweezers,  for  solder,  etc. 
Pteamer,  for  countersink. 
Blow-pipe,  mouth. 

Pumice  block  for  soldering. 
Lathe,  cone-bearing, 
polish-  Circular  saw,  large  and  small 
bur,  and  drills. 

Two  ladles. 

Stick  for  packing. 

Two  sizes  of  rings  for  counter 
die. 

used  for  soldering,  “  waxing 


up,”  vulcanizing  and  melting  metals. 


FOR  RUBBER  WORK. 

Vulcanizer.  Flasks. 

Wrenches.  Press. 

Scraper,  round  shape.  Chisel,  with  narrow,  thin  edge. 

Small  pointed  instruments  for  for  trimming  around  necks 
finishing  between  the  teeth.  of  teeth. 

Saw-frame  and  saws.  Calipers. 

An  instrument  for  waxing  up.  Files,  two  grades, 
straight  and  pointed  at  one  Plaster-knife, 
end,  and  slightly  curved  at  Heavy  tea  or  dessert  spoons 
the  other.  for  mixing  and  handling 

Bowls,  medium  size.  plaster. 

Shellac  bottle,  (wide  mouth.)  Oil  bottle. 

FOR  CELLULOID. 

All  tools  used  for  rubber  except  vulcanizing  flasks  and  press, 
substituting  celluloid  flasks  and  press. 


FOR  CONTINUOUS  -  GUM. 

Furnace.  Mutfles,  slides,  tongs,  and 

Porcelain  Boxes,  for  mixing  poker. 

material.  Camel  hair  pencils. 


6 


student’s  manual 


Instruments  for  applying  ma-  Stiff  Brushes. 

terial. 

To  the  above  can  be  added : 

Automatic  blow-pipe.  Bolling  Mill. 

Furnace  or  melting  apparatus.  Tongs  for  crucible. 

Ingot  Mold.  Plate  gauge. 

Cutting  pliers.  Curved  shears. 

BLOW-PIPE,  ETC. 

Every  student  should  learn  to  use  the  mouth 
blow-pipe. 

The  first  thing  to  be  done  is  to  secure  a  proper 
blow-pipe.  Those  usually  sold  at  the  depots  are 
made  for  jewelers,  who  solder  small  objects  with  a 
low  grade  of  solder,  and  not  invested  as  teeth  are. 
The  S.  S.  White  Co.  and  Welch  Dental  Co.  have  now 
blow-pipes  made  recently,  at  my  suggestion.  The 
mouth  aperture  is  I  and  the  small  one  tV  inch. 

The  end  should  not  be  taken  between  the  lips,  as  it 
tires  the  muscles  too  much,  but  pressed  against  them. 
There  must  be  a  supply  of  air  in  the  lungs  constant¬ 
ly,  so  do  not  allow  a  complete  collapse  of  the  dia¬ 
phragm,  at  the  same  time  pressing  the  tongue  against 
the  palate  to  prevent  the  lips  collapsing  while  draw¬ 
ing  in  a  fresh  supply  through  the  nose.  A  little  prac¬ 
tice,  observing  these  rules,  will  soon  enable  you  to  use 
it  successfully. 

The  automatic  blow-pipe,  operated  by  foot  bellows, 
is  very  useful  to  those  who  cannot  use  the  mouth  blow¬ 
pipe. 


AND  HAND-BOOK. 


7 


The  proper  form  of  gas  jet  for  soldering  is  a  wire 
bulb,  made  by  leaving  the  end  of  the  gas-pipe  with 
no  burner  and  winding  over  it  fine  binding-wire,  till 
a  bulb  about  1  inch  in  diameter  is  secured ;  the  same 
results  may  be  obtained  by  making  a  bulb  of  several 
thicknesses  of  fine  wire-gauze  over  the  end  of  the  pipe, 
and  bound  tightly  to  it.  The  object  is  to  break  the 
force  of  the  gas,  and  add  more  oxygen  to  it ;  in  this 
way,  a  flame  like  an  alcohol  lamp  is  secured,  which 
can  be  easily  controlled  by  the  blow-pipe,  and  in  heat¬ 
ing  up,  the  whole  flame  can  be  taken  within  its  scope. 
The  gas  fixture  should  be  horizontal,  with  two 
lengths,  so  as  to  place  in  the  most  convenient  position 
while  using. 


CHAPTER  IV. 


IMPRESSIONS. 

0 

HE  success  of  the  artificial  denture  depends  on  a 
correct  impression  as  the  foundation  for  the 
work,  therefore  care  should  be  taken  to  insure  success. 
As  to  materials,  I  differ  with  many  instructors.  In 
some  cases,  good  impressions  can  be  taken  in  wax, 
more  in  the  modeling  compound,  but  plaster  is  a 
material  always  to  be  relied  on.  It  may  be  accepted 
as  an  axiom  that  the  more  difficult  the  case  to  obtain 
an  impression  of,  the  greater  need  of  plaster. 


8  student’s  manual 

For  a  Full  Upper,  spread  a  large  napkin  over  the 
dress;  select  a  cup  as  near  the  size  of  the  jaw  as  possi¬ 
ble;  as  it  is  necessary  to  obtain  a  high  impression 
over  the  cuspids,  place  a  little  wax  over  the  outside 
of  the  cup  at  those  points,  also  over  the  posterior 
corners,  if  the  process  is  deep,  and  raise  the  palatal 
surface  at  the  rear  a  little,  if  the  arch  is  deep. 

Mix  the  plaster  to  the  consistency  of  thick  cream, 
and  add  a  pinch  of  salt,  at  the  last  moment,  after  the 
plaster  is  ready,  as  you  do  not  want  to  hasten  the 
setting  till  after  placing  in  the  mouth ;  stand  at  the 
right  side,  and  with  the  left  hand  distending  the  lips, 
press  the  rear  of  the  cup  into  place,  and  so,  forcing 
any  excess  forward,  press  the  cup  full  into  place,  at 
the  same  time  telling  the  patient  to  “keep  the  tongue 
quiet,  and  not  to  be  concerned  about  what  runs  over 
at  the  rear,’’  then  pressing  the  lip  so  as  to  force  the 
plaster  well  up  under  it.  If  there  is  nausea,  tell 
the  patient  to  resist  the  tendency,  as  it  will  be  over  in 
a  few  moments.  As  soon  as  the  plaster  has  set,  which 
can  be  ascertained  by  breaking  off  a  piece  of  the 
surplus  in  front,  remove  by  raising  the  lip  high,  and 
working  the  impression  so  as  to  let  in  the  air. 

For  a  Full  Lower,  proceed  as  above,  only  standing 
in  front  of  the  patient,  and  as  the  cup  is  passed  into 
place,  press  the  cheeks  away  from  the  cup,  so  there 
shall  not  be  a  fold  of  membrane  underneath. 

For  a  Partial  Lower,  with  the  anterior  teeth  remain- 


AND  HAND-BOOK. 


9 


ing,  select  a  cup  with  an  opening  for  the  teeth,  and 
through  which  they  will  pass  easily.  Wet  a  piece  of 
paper  and  lay  over  the  opening,  and,  holding  the  cup 
in  the  palm  of  the  hand,  put  in  the  plaster,  and  place 
in  the  mouth,  always  pressing  away  the  plaster  from 
the  front  before  inserting,  so  as  to  have  as  little  out¬ 
side  of  the  teeth  as  possible,  as  it  will  facilitate  its  re¬ 
moval.  If  there  are  molars  remaining,  so  that  the 
sides  of  the  cup  will  not  go  deep  enough,  place  wax 
on  the  outer  edges.  Sometimes  the  teeth  stand  in  such 
a  position  that  the  plaster  must,  of  necessity,  break  ; 
this  is  of  little  importance,  as  the  pieces  will  readily 
go  together  again. 

For  a  Partial  Upper ^  proceed  as  with  a  full  upper, 
only,  before  inserting,  press  away  the  plaster  from  the 
sides  of  the  cup  where  there  are  teeth,  as  there  will  be 
enough  to  go  outside.  Do  not  let  the  plaster  set  as 
hard  as  in  full  cases,  or  the  cup  will  leave  the  impres¬ 
sion,  and  the  plaster  have  to  be  broken  away  in  pieces. 
This  can  always  be  avoided,  and  should  be,  as  it  is 
very  unpleasant  for  the  patient. 

Never  take  an  impression  in  wax,  and  then  plaster 
in  it,  for  while  the  plaster  will  break  just  the  same,  it 
will  often  be  difficult  to  replace,  or  even  save  the 
pieces,  when  they  are  thin;  there  is  nothing  to  be 
gained  by  it.  Be  sure  your  impression  is  good  before 
dismissing  the  patient.  It  is  a  simple  process,  only 
avoid  using  an  excess  of  plaster,  and  too  large  a  cup. 


10 


student’s  manual 


CHAPTER  V. 


PLASTER  CASTS. 

$"HILE  there  are  various  methods  of  preparing 
the  impression,  I  much  prefer  shellacking,  al¬ 
ways  using  it  thin,  so  it  will  strike  in,  and  not  make 
a  skin  on  the  surface.  By  shellacking,  it  is  easy  to 
tell  what  is  cast  and  what  is  impression,  when  sepa¬ 
rating.  Next,  oil  lightly,  and  turn  the  impression 
down  while  mixing  the  plaster.  Mix  the  plaster  the 
same  as  for  the  impression,  about  the  consistency  of 
thick  cream ;  place  but  little  in  the  impression,  at 
first,  and  jar  thoroughly  so  as  to  drive  out  all  air. 
When  hard,  remove  the  cup,  and  with  a  sharp  knife, 
pare  the  impression  to  near  the  teeth,  if  there  are  any, 
or  to  the  cast.  With  a  blunt-pointed  knife,  proceed 
to  break  it  away,  beginning  at  the  heel  and  pressing 
with  the  thumb  to  guard  against  the  knife  going  into 
the  cast. 

For  a  full  upper,  make  the  following  changes  in  the 
cast.  In  most  cases,  the  palate  is  hard  in  the  centre, 
and  as  the  rest  of  the  surface  will  yield  invariably  to 
pressure,  the  plate  will  bear  hard  and  irritate,  and 
rock.  Therefore  relief  should  be  provided  by  raising 
the  plate  where  the  palatal  bone  is  hard.  If  it  is 
to  be  a  rubber  plate,  scrape  a  portion  from  the  plate 


AND,  HAND-BOOK. 


11 


when  finishing.  For  a  metal  plate,  it  is  better  to 
raise  with  a  thin  film  of  wax  along  the  entire  hard 
palate,  about  inch  in  depth,  graduating  to  the 
edges  so  as  to  show  no  line.  The  amount  of  surface 
thus  covered  will  vary  in  different  mouths ;  some  quite 
wide,  others  narrow.  At  each  side  of  the  hard  palate, 
at  the  posterior  edge  of  tiie  plate,  scrape  the  cast 
slightly,  so  the  plate  will  hug  snugly  there  (Fig.  2.) 


If  there  is  a  flexible  ridge  in  front,  its  normal  con¬ 
dition  is  where  the  plate  which  has  been  worn  has 
pressed  it,  and  there  it  should  remain,  for  no  change 
of  position  will  improve  it ;  it  would  be  better  if  the 
patient  would  submit  to  its  removal. 

No  air  chambers  are  needed  in  full  plates.  If  the 
plate  comes  in  close  contact  with  the  membrane, 
there  will  be  all  the  adhesion  necessary  to  sustain  the 
heaviest  work. 


12 


student’s  manual 


Mix  plaster,  spread  on  a  smooth  surface,  and  set  the 
cast  into  it,  so  as  to  make  the  whole  about  inches 
high  ;  if  the  cast  is  slightly  under-cut,  raise  the  front  a 
little,  and  then  form  the  plaster  around  the  sides  so 
as  to  have  them  flaring.  The  object  is  to  facilitate 
the  removal  of  the  cast  from  the  mold,  as  it  will  de¬ 
liver  itself  better  than  if  removed  with  the  fingers. 

If  the  case  is  badly  undercut,  either  in  front  or  at 
the  posterior  corners,  make  a  “core”  (Fig.  3)  as  fol¬ 


lows  :  Set  the  cast,  after  it  is  ready  for  molding,  on 

a  smooth  surface;  oil  the  surface,  where  under-cut; 
mix  plaster  and  asbestos,  equal  parts,  and  lay  on  the 

surface  i  inch  wide  at  the  base,  up  to  the  top  of  the 
cast ;  when  hard,  remove,  trim,  and  dry  perfectly  for 
molding. 

For  full  lower,  prepare  for  molding  as  above,  hav- 


AND  HAND-BOOK. 


13 


ing,  previously  to  filling  the  impression,  removed  a  lit¬ 
tle  from  the  surface  of  it,  in  the  extreme  depression,  or 
what  represents  the  summit  of  the  jaw,  so  the  plate 
will  set  more  easily. 

If  the  lower  case,  either  full  or  partial,  is  badly 
under-cut,  make  a  “  core,”  in  two  sections,  one  trans¬ 
versely  across  the  heel  to  past  the  cuspid,  and  the 
other  to  lap  on  to  this  one.  In  this  way  a  perfect  die 
may  be  obtained  (Fig.  4). 


If  it  be  a  partial  lower,  leave  the  anterior  teeth  on 
the  cast,  building  up  with  plaster  against  the  front  to 
have  the  cast  fiare,  cutting  off  all  other  teeth  from 
the  cast. 

For  partial  uppers  cut  off  all  teeth.  If  for  suction, 
relieve  the  hard  centre,  as  in  full  sets ;  or  if  deemed 
best,  put  in  an  “air-chamber.”  Some  patients  will 
wear  a  plate  without,  others  will  think  they  cannot. 


14 


student’s  manual 


CHAPTER  VI. 


DIES. 

tHE  qualities  requisite  for  a  dental  die  are  these: 

non-shrinking ;  hard,  so  as  not  to  batter  in  swag¬ 
ing  ;  cohesive,  so  as  not  to  break ;  furnishing  a  smooth 
surface  ;  fusing  at  a  low  temperature. 

Babbitt  metal  is  the  only  alloy  that  furnishes  all  of 
these  qualities.  My  use  of  it  for  35  years  has  fully 
demonstrated  its  complete  adaptability  to  this  use. 
But  as  there  are  many  formulas,  it  is  important  to 
have  one  suited  to  this  purpose.  This  is,  copper  1 
part,  antimony  2  parts,  tin  8  parts.  These  should 
be  melted  in  the  order  named,  as  tin  would  oxidize 
badly  before  the  first  was  melted  if  all  were  placed  in 
the  crucible  together.  As  a  strong  heat  is  required,  it 
is  well  to  use  a  furnace,  or  a  blacksmith’s  forge.  Melt 
and  turn  off  into  ingots,  and  re-melt.  Babbitt,  made 
from  this  formula,  can  be  had  of  the  leading  dental 
supply  manufacturers.  If  it  should  not  be  found  to 
run  freely  from  the  ladle,  when  making  a  die,  add 
some  tin. 

For  Counter  Dies.  As  lead  fuses  at  a  higher  tem¬ 
perature  than  Babbitt,  and  would  adhere  to  it  when 
the  lead  was  poured  on  it,  you  must  reduce  the  melt¬ 
ing  temperature  by  the  addition  of  tin, — 5  parts  lead. 


AND  HAND-BOOK. 


15 


1  part  tin ;  tins  also  hardens  it,  which  is  an  advantage, 
as  lead  is  too  soft. 

The  use  of  oiled  sand  will  be  found  an  advantage, 
because  it  can  be  used  a  great  many  times,  when 
properly  prepared,  avoids  bubbling  and  other  delays 
incidental  to  wetting  sand,  to  say  nothing  of  the 
annoyance  incidental  to  the  use  of  it. 

Use  sweet  oil,  making  the  sand  of  the  same  consist¬ 
ency  as  when  wet.  If  too  much  is  in,  add  more  sand. 
Avoid  the  use  of  sand  which  is  very  fine. 

The  molding-box,  ring,  and  flasks  have  been  de¬ 
scribed  in  a  previous  chapter  (II.).  It  is  necessary  to 
sift  the  sand  only  after  using  several  times,  and  then 
only  on  the  surface  of  the  model.  Pack  hard  at  first 
around  the  sides,  so  the  sand  will  not  drop  out  of  the 
ring,  and  then  gradually  adding  and  packing  till  full. 
In  most  cases,  the  model  will  drop  when  lifting  the 
mold.  If  it  does  not,  jar  the  edge  of  the  ring  on  the 
edge  of  the  molding-box.  A  potato-masher  is  well 
adapted  for  packing  the  sand,  using  the  small  end  for 
the  sides,  and  large  end  for  the  top. 

It  is  a  good  plan  to  rub  pulverized  soap-stone  on 
the  model  before  molding,  especially  when  the  sand  is 
first  used. 

Melt  the  Babbitt,  and  do  not  pour  when  very  hot, 
but  stir  till  it  has  cooled  a  little,  so  it  will  not  burn 
the  sand  much. 

Be  careful  not  to  injure  the  metal  by  over-heating 


16 


student’s  manual 

it.  Do  not  cool  the  die  suddenly  in  water,  as  it  tends 
to  make  it  brittle. 

After  it  is  cool,  coat  with  whiting,  wetting  and  rub¬ 
bing  it  on  with  the  finger.  Set  it  into  the  sand  half 
its  depth ;  place  a  small  ring  or  flask  around  it ;  melt 
the  lead  and  turn,  but  do  not  fill  the  ring  full,  leaving 
space  to  grasp  it  with  pliers,  and  plunge  into  water. 
It  is  never  necessary  to  swage  in  the  ring. 

In  molding  an  under-cut  case,  put  the  “  core  ”  care¬ 
fully  in  place,  and  mold  as  before;  the  whole  will 
drop  out ;  replace  carefully  the  core,  mold,  and  cast. 

When  cores  are  needed  at  the  posterior  corners,  or 
in  lower  cases,  before  making  the  counter  die,  pack  a 
little  sand  into  the  under-cut,  so  the  die  and  counter 
will  separate ;  then,  after  the  plate  has  been  partially 
swaged,  bring  the  plate  into  place  in  the  under-cut 
with  the  burnisher,  or,  if  necessary,  with  a  round- 
faced  hammer. 

It  is  sometimes  necessary  to  make  a  second  die,  but 
not  generally  where  Babbitt  is  used. 

If  the  case  has  a  deep  arch,  make  a  half  counter, 
just  filling  the  arch,  and  not  extending  on  the  ridge  ; 
by  so  doing  there  is  less  danger  of  tearing  the  plate 
in  the  arch,  when  swaging. 


AND  HAND-BOOK. 


17 


CHAPTER  VII. 


SWAGING  PLATES. 


^  ITT  a  pattern  for  the  desired  plate  ;  for  this  there 
^  is  nothing  so  good  as  Japan  tea-chest  lead ;  it  is 
thicker  and  stronger  than  the  Chinese. 

The  grain  of  the  plate  should  always  be  crosswise 
of  the  die,  as  in  the  swaging  there  is  far  less  danger  of 
its  tearing,  and,  of  course,  is  stronger  in  wear. 

Oil  the  dies  to  prevent,  as  far  as  may  be,  base  metal 
from  adhering  to  the  plate ;  if  metal  adheres,  wipe  it 
off,  as  it  will  eat  into  the  plate  when  heating. 

Anneal  by  heating  to  redness ;  as  the  surface  oxi¬ 
dizes,  clean  by  dropping  while  hot  into  equal  parts 
water  and  sulphuric  acid.  For  an  acid  dish  there  is 
nothing  so  good  as  lead ;  it  is  easily  made  by  forming 
it  of  thick  sheet  lead,  over  anything  of  proper  size, 
about  4  inches  diameter,  1  inch  deep,  with  a  handle 
cut  in  the  same  piece.  Sulphuric  acid  can  be  boiled 
in  these,  and  they  will  last  for  years. 

If  the  case  is  a  fidl  upper,  use  the  mallet  in  the 
arch,  and  if  deep,  swage  with  the  half  counter ;  the 
bending  pliers  (lower  always)  will  be  found  of  value 
in  shaping  the  ridge ;  to  save  time,  and  against  which 
there  is  no  possible  objection,  cut  the  edge  of  the 


18 


student’s  manual 

plate  in  front,  lap,  and  after  fully  swaging,  solder. 
If  the  plate  is  soft,  like  20  karat,  or  platina,  twice 
annealing  is  sufficient,  ordinarily ;  always  cleanse  in 
the  acid  after  annealing.  There  is  danger  of  over¬ 
swaging. 

If  the  case  is  under-cut,  after  full  swaging,  place  on 
the  plaster  cast  and  burnish  into  the  depression  more 
fully.  With  the  Babbitt  metal  die  it  will  be  seen 
that  the  plate  fits  the  plaster  cast  snugly,  so  much  so 
that  sometimes  it  will  not  come  full  up  to  the  cast  in 
the  centre;  it  will  however,  come  to  its  bearings  at 
that  point  in  the  mouth. 

To  aid  in  restoring  the  contour  of  the  lip,  trim  al¬ 
ways  so  as  to  have  the  highest  points  over  the  cuspids, 
but  drop  suddenly  back  of  those  points  so  as  to  give 
free  play  to  the  muscles  (Fig.  5).  The  plate  can 


Figure  5. 


AND  HAND-BOOK. 


19 


seldom  be  worn  as  high  as  the  impression  indicates 
back  of  these  points,  but  leave  the  plate  high  enough, 
so  that  on  trying  in,  it  can  be  trimmed  as  desired. 
Be  sure  there  is  room  for  the  frsenum  by  cutting  or 
filing  an  opening  for  it.  Always  extend  the  plate 
over  the  maxillary  tuberosities,  however  large,  as  it 
aids  in  keeping  the  plate  in  place,  preventing  its 
slipping  forward. 

The  edge  of  a  plate  should  never  be  swaged  to  form 
a  “  rim,”  because  the  edge  should  be  left  for  trimming 
by  the  mouth.  If  a  rim  or  binding  is  needed,  solder 
one  on ;  it  is  easily  done,  and  looks  better. 

In  swaging  a  lower  plate,  use  the  bending  pliers 
first.  If  the  gum  is  flat,  it  is  well  to  swage  in  two 
pieces,  overlapping  at  least  an  inch,  thus  doubling  the 
plate  where  it  needs  strengthening. 

In  trimming  a  lower  plate,  it  should  be  remembered 
that  much  trouble  arises  from  its  being  made  too 
deep,  so  as  to  infringe  on  the  muscles  and  loose  integu¬ 
ment.  The  plate  is  thus  lifted  by  them,  and  they  in 
return  are  irritated  by  the  plate. 

In  swaging  a  partial  lower,  the  jolate  should  be 
swaged  in  two  pieces,  as  it  facilitates  the  process,  and 
doubles  it  where  needed.  Cut  each  pattern  so  as  to 
extend  from  the  posterior  to  2  inch  beyond  the  cuspid, 
or  bicuspid  if  any  remain.  Always  carry  the  plate 
above  the  necks  of  the  teeth,  about  half  way,  as  often 
the  attachment  of  the  muscle  is  so  high  it  necessitates 


20 


student’s  manual 


making  the  plate  very  narrow,  unless  it  is  carried 
higher,  and  it  will  set  firmer  for  so  doing. 

Swage  each  piece  separate,  and  then  swage  to¬ 
gether,  putting  borax  between ;  clamp  with  small  wire 
clamps  (hair  pins  make  good  ones) ;  one  of  the  pieces 
will  usually  overlap  the  other,  or  if  it  does  not,  both 
may  need  trimming ;  trim  one,  leaving  the  overlap  on 
the  other  till  after  soldering,  so  as  to  lay  the  solder  on 
the  overlap,  drawing  through  till  it  can  be  seen  on  the 
other  edge. 

In  swaging  a  partial  upper,  use  the  mallet  first,  and 
the  bending  pliers  if  needed. 

If  it  is  to  be  a  clasp-plate,  extend  the  plate  I  inch 
beyond  the  tooth  to  be  clasped,  as  the  plate  mil  set 
steadier.  Double  around  weak  points,  either  each 
tooth  separately,  or  in  one  piece  I  inch  wide  around 
the  whole  plate,  laying  the  solder  on  the  overlapping 
points,  and  drawing  through ;  as,  if  lain  on  the  inner 
edge,  there  is  danger  of  flowing  it  on  the  plate.  It  is 
never  well  to  double  the  whole  plate. 


AND  HAND-BOOK. 


21 


CHAPTER  VIII. 


f 


FITTING  PLATES. 

N  tlie  full  upper  plate,  see  that  it  sets  steady.  If 
the  ridge  is  flexible,  it  must  inevitably  yield  to 
pressure.  The  point  of  great  importance  is  at  the 
posterior  margin,  in  the  centre.  See  that  it  sets  close 
enough  to  exclude  the  air.  This  can  be  done  by 
wetting  it  before  placing  in  the  mouth,  and  then  by 
a  pumping  process,  watching  for  the  escape  of  air-bub¬ 
bles.  It  is  equally  necessary  to  see  that  it  does  not 
press  so  hard  at  that  point  as  to  irritate,  and  then 
loosen ;  this  is  often  the  case. 

After  trimming  the  outer  margin,  turn,  with  the 
pliers,  the  extreme  edge  about  of  an  inch,  to  guard 
against  irritation.  Plates  can  be  worn  higher  than 
many  dentists  imagine,  judging  by  the  way  they  are 
usually  trimmed.  They  should  be  worn  as  high  as 
possible,  especially  over  the  cuspids. 

In  fitting  a  partial  upper  plate,  see  that  it  does  not 
infringe  on  the  necks  of  the  teeth,  wearing,  making 
them  sore,  and  displacing  them,  and  preventing  the 
plate  coming  to  its  place  on  the  membrane. 

In  fitting  a  full  lower  plate,  see  that  it  sets  steady ; 
have  the  patient  raise  the  tongue  to  the  palate,  and 


22 


student’s  manual 


see  if  it  lifts  the  plate ;  then  lift  the  lip  in  front  and 
at  the  sides,  and  if  there  is  interference,  trim  accord¬ 
ingly. 

In  fitting  a  partial  lower,  see  that  it  does  not  press 
hard  against  the  teeth,  but  lays  easily,  and  observe 
the  rules  in  the  full  lower. 

Always  be  satisfied  that  your  j^lates  fit  before 
taking  further  steps. 


CHAPTER  IX. 


CLASPS. 

fHE  use  of  clasps  is  not  objectionable  if  properly 
^  adapted,  and  kept  clean.  Often,  when  bridge 
work  is  used,  a  nicely  adj  usted  narrow  plate,  properly 
clasped,  would  be  far  less  objectionable  than  permanent 
fixtures,  saving,  instead  of  destroying,  the  teeth  at¬ 
tached  to. 

Clasps  should  not  be  so  wide  as  to  cover  a  large 
portion  of  the  tooth,  being  cumbersome,  and  looking 
badly.  Neither  should  they  be  very  narrow,  as  is 
the  custom  with  English  dentists,  as  they  wear  into 
the  enamel. 

As  a  rule,  about  -I-  to  inch  wide  is  sufficient. 
The  material  should  be  18  karat  alloyed  with  platina, 
so  as  to  be  springy;  in  thickness  about  24  gauge. 


AND  HAND-BOOK. 


23 


In  selecting  teeth  for  clasping,  the  second  bicuspids 
are  preferable,  if  the  way  is  clear  for  using  them,  be¬ 
cause  of  their  straight  sides,  and  being  in  a  position 
to  sustain  the  plate  in  balance.  The  first  bicuspid  is 
to  be  chosen,  if  there  is  no  second,  especially  if  there 
is  to  be  a  small  plate  of  few  teeth.  The  first  molar 
next,  especially  if  it  is  a  large  plate. 

It  is  not  advisable,  except  in  rare  instances,  to 
wedge  or  file  teeth  for  the  purpose  of  using  clasps. 

If  those  to  be  clasped  to  are  the  only  teeth  left  of 
the  upper  set,  the  danger  that  eventually  they  may 
be  lost  would  indicate  the  advisability  of  making  a 
suction  plate,  so  that  the  plate  would  still  be  useful, 
but  while  they  remain,  use  them  to  steady  the  plate 
in  masticatiom 

Fit  the  clasps  to  the  plaster  teeth  as  accurately  as 
possible  ;  then  fit  them  to  the  natural  teeth ;  if  the 
clasp  is  on  a  bicuspid,  do  not  let  it  pass  in  the  front 
if  it  can  pass  around  the  back ;  in  other  words  avoid 
its  showing  if  possible.  If  it  is  on  a  molar,  and  can 
pass  all  around,  let  the  ends  meet  at  the  labial  surface. 
After  fitting,  press  open  slightly  so  as  to  remove  easily  ; 
with  wax  firmly  attached  to  the  plate,  unite  the  two, 
and,  placing  in  the  mouth,  press  both  into  j^lace,  and 
carefully  remove.  Invest  the  clasp  and  a  small  por¬ 
tion  of  the  plate  in  plaster  and  pumice ;  warm  and 
remove  the  wax  ;  fasten  the  plate  and  investment  to¬ 
gether  with  a  wire  clamp,  so  that  they  may  not 


24 


student’s  manual 


become  separated  while  heating ;  if  there  is  a  space 
between  the  clasp  and  plate,  as  it  is  sometimes  not 
advisable  to  put  the  clasp  high  up  on  the  tooth,  put  a 
piece  of  gold  in  when  soldering  the  clasp  to  the  plate. 
Never  unite  them  for  a  space  of  more  than  one-eighth 
to  three-sixteenths  of  an  inch,  thus  leaving  full  play 
for  the  elasticity  of  the  clasp.  To  j)revent  the  solder 
flowing  beyond  this  point,  put  plaster  into  the  joint. 

Adjust  but  one  clasp  at  a  time,  and  round  and  thin 
the  ends  slightly  in  flnishing. 


CHAPTER  IX. 

INVESTING,  BACKING,  SOLDERING. 

^  T  is  well  to  have  several  sizes  of  sheet-iron  rings,  one 
^  inch  deep,  to  invest  in.  Select  one  a  little  larger 
than  the  case,  then  there  will  not  be  superfluous  plas¬ 
ter  to  heat  up  and  keep  hot ;  and  the  case  is  secure 
from  accident  in  handling. 

Mix  equal  parts  of  plaster  and  sand  (some  use  as¬ 
bestos,  but  it  is  more  expensive,  and  is  not  so  solid  to 
back-up  in).  Be  sure  it  comes  in  contact  with  the 
plate,  for  if  there  is  a  space  underneath,  there  will  be 
danger  of  melting  a  hole  in  it.  When  hard,  warm 


AND  HAND-BOOK. 


25 


and  remove  the  wax,  then,  setting  it  in  the  sink,  dash 
hot  water  on  it. 

I  prefer  backing  in  the  investment,  as  it  avoids  the 
necessity  of  investing  separately  and  heating  up  and 
soldering  twice,  and  it  can  be  done  as  well  as  by  the 
other  method. 

For  backing,  the  gold  should  be  thicker  than  the 
plate.  I  use  clasp  material.  Cut  off  a  strip  the  width 
of  the  teeth  ;  shape  the  end  to  the  plate  ;  put  color¬ 
ing,  ink,  or  other  material,  on  the  head  of  the  pin, 
and  press  the  gold  on  it,  and  punch ;  enlarge  the  sur¬ 
face  of  the  opening  with  a  small  “  countersink if  it 
is  a  back  tooth,  cut  off  the  gold  even  with  the  crown  ; 
if  a  front  tooth,  it  looks  better  a  little  shorter,  with 
the  ends  rounded  and  chamfered.  If  they  are  gum 
teeth,  shape  to  the  shoulder  on  the  gum,  and  let  them 
meet  only  at  that  point.  If  plain  teeth,  do  not  let 
them  meet  at  all.  After  it  is  fitted,  bend  slightly  so 
it  will  fit  snugly,  and  with  a  sharp  chisel-shaped  in¬ 
strument  split  the  head  of  the  pin  ;  it  is  better  never 
to  rivet,  as  if  only  split  the  solder  will  flow  around 
the  pin  in  the  hole,  and  fasten  more  securely  than 
riveting.  It  is  well  to  cut  off  the  head  of  the  pin,  if 
too  long,  before  putting  on  the  backing. 

If  there  are  spaces  under  the  teeth,  fill  with  foil. 
These  should  be  avoided,  as  far  as  possible,  by  close 
grinding. 

See  that  the  surface  of  the  plate  is  clean  ;  mix  pul- 


26 


student’s  manual 

verized  borax  on  a  slate  or  glass,  having  it  sufficiently- 
wet  to  spread  easily ;  I  prefer  for  use  a  thin  stick. 
Cut  the  solder  small  and  lay  it  where  you  wish  it  to 
flow.  Place  it  to  heat  over  the  gas,  and  let  it  heat 
slowly  for  fifteen  minutes,  then  turn  on  the  full  heat, 
and  when  as  hot  as  that  will  make  it,  place  in  a  small 
soldering  pan  (Fig.  6),  and  throw  a  full  blast  on  it. 


Figure  6. 


heating  equally  plate  and  backing,  till  the  solder 
flows.  If  the  solder  is  what  it  should  be,  it  will  sweat 
down  where  it  lays  and  blend  in  with  the  plate.  To 
insure  this,  the  solder  should  be  of  the  same  karat  as 
the  plate,  18  to  20.  The  nearer  the  melting  point  of 
the  plate,  the  better  the  results  and  the  less  labor  in 
finishing. 


AND  HAND  BOOK. 


27 


The  entire  surface  of  the  plate  should  be  exposed. 
If  it  is  a  lower  partial,  cut  out  the  plaster  iu  the  centre 
entirely,  so  there  will  be  an  opening  to  prevent  the 
flame  rebounding. 


CHAPTEK  XI 


FINISHING  METAL  PLATES. 


S  soon  as  cool,  place  in  water  to  soften,  and  re- 


v]V  move  the  investment,  and  place  in  the  acid  to 
boil ;  then  clean  the  plate  and  removes  the  borax. 
Next  place  the  plate  in  a  solution  of  soda  to  remove 
the  acid  from  under  the  teeth. 

With  the  file  remove  all  sharp  corners  and  edges  ; 
with  fine,  small  corundum  smooth  the  surface  over 
the  pins  and  wherever  the  solder  has  not  flowed  pro¬ 
perly. 

Drive  a  pine  stick  into  the  chuck  hole  of  the  lathe, 
and  with  a  sharp  pocket  knife  turn  it  to  a  round 
point ;  then  with  pumice  finish  the  entire  surface,  fol¬ 
lowing  with  small-sized,  soft  brush-wheels,  and  finally 
with  whiting  or  rouge. 


28 


student’s  manual 


CHAPTER  XII. 


PREPARATIONS  OF  METALS  AND  MAKING  SOLDERS. 

F  a  dental  depot  is  easy  of  access,  better  buy  than 
-fl  prepare  plate  and  solder ;  jewelers  are  not  as 
expert  in  preparing  them. 

Gold  plates  of  a  lower  karat  than  18  should  never 
be  used  ;  I  prefer  20.  It  should  be  made  with  pure 
gold  alloyed  with  pure  copper  and  silver,  one  part  of 
the  former  to  two  of  the  latter.  For  20  karat,  1  ounce 
of  gold  and  4  dwt.  of  the  alloy  ;  for  18  karat,  1  ounce 
of  gold  and  6  dwt.  of  the  alloy. 

Place  in  a  crucible  with  plenty  of  borax,  and  melt, 
and  turn  into  the  ingot  mold.  Roll  lengthwise  to  the 
necessary  width  of  plate ;  then  anneal,  and  roll  to 
gauge  28,  which  is  a  suitable  thickness  for  all  plates, 
except  lower,  which  should  be  thicker,  additional 
strength  in  special  cases  being  obtained  by  doubling. 

To  Dispose  of  Scraps,  Filings,  and  Old 
Plates. — Save  all  clean  scraps  and  portions  of  old 
plates  that  are  free  from  backings,  clasps,  and  solder, 
and  melt.  All  else,  including  filings,  through  which 
a  small  horseshoe  magnet  has  been  passed  to  remove 
steel  particles,  should  be  subjected  to  a  strong  heat 
with  saltpetre.  If  it  does  not  come  out  tough,  sub¬ 
ject  it  to  corrosive  sublimate.  If  this  does  not  do, 


AND  HAND-BOOK. 


29 


send  to  an  expert.  This  product  usually  has  enough 
platina  in  it  for  clasp  and  backing  material. 

To  make  clasp  gold,  take  20  karat  plate  and  add  2 
dwts.  platina.  Melt  the  gold,  and,  rolling  the  platina 
as  thin  as  possible,  drop  into  the  gold  when  melted. 
The  gold  acts  as  a  flux,  and  the  platina  is  melted. 

Gold  Solder. — The  leading  dental  depots  pro¬ 
vide  now  an  admirable  quality  of  solder.  But  if  you 
wish  to  make  it,  the  following  recipe,  by  an  old  ex¬ 
pert,  Dr.  D.  H.  Goodno,  makes  a  solder  that  has  all 
the  qualities  desired,  being  remarkably  tough,  flows 
readily,  and  does  not  discolor  in  the  mouth.  He 
says  he  has  rolled  it  as  thin  as  a  ribbon  of  pure  gold : 
40  grains  pure  gold,  2?  grains  pure  silver,  2i  grains 
pure  copper,  3  grains  pure  zinc ;  roll  the  zinc  in  gold 
foil  and  place  in  the  bottom  of  the  crucible ;  cover 
with  borax ;  cut  the  other  material  fine  and  place  in 
the  crucible,  and  cover  with  borax ;  melt  and  roll. 

Another  recipe  is  made  as  follows,  by  first  making 
an  alloy :  3  dwts.  pure  silver,  3  dwts.  pure  coj^per, 
dwts.  pure  zinc.  Roll  the  zinc  in  gold  foil  and  place 
in  the  crucible,  and  cover  with  borax ;  place  the  cop¬ 
per  and  silver  on  it  and  cover  with  borax,  and  melt ; 
roll  thin,  and  use  according  to  the  karat  you  wish ; 
for  20  karat  5  dwts.  pure  gold,  1  dwt.  alloy;  for  18 
karat  (and  there  is  no  necessity  for  using  a  lower 
karat  in  the  mouth),  5  dwts.  gold,  dwts.  alloy. 
Always  test  your  solder  by  flowing  on  silver  plate. 


30 


student’s  manual 


SiLVEE. — For  partial  sets,  when  the  patient  cannot 
afford  gold,  silver  makes  a  good  substitute.  But  coin 
silver  should  never  be  used,  as  it  oxidizes  badly  in 
the  mouth.  Pure  silver,  alloyed  with  platina,  makes 
a  good  plate,  which,  of  course,  discolors  from  the 
presence  of  sulphuretted  hydrogen  in  the  mouth,  but 
is  easily  cleaned ;  2  dwts.  of  platina  to  the  ounce  of 
silver  is  sufficient. 

For  clasps  for  silver  plate  use  gold ;  and  I  prefer 
to  solder  with  gold,  using  18  karat.  Silver  solder  is 
made  as  follows  :  Silver,  6  parts ;  copper,  3  parts ; 
zinc,  2  parts ;  melting  the  copper  and  silver  and  then 
adding  the  zinc. 


CHAPTER  XIII. 


ATTACHMENT  OF  TEETH  TO  PLATES. 


S  a  rule,  in  partial  sets,  the  teeth  should  be  backed 
and  soldered. 


In  full  upper  sets,  it  is  no  longer  necessary  to  use 
the  single  gum  teeth,  and  it  is  not  advisable,  for  it  is 
impossible,  with  them,  to  secure  proper  arrangement, 
articulation,  and  restoration  of  contour ;  besides,  the 
work  is  not  cleanly,  on  account  of  secretions  getting 
between  the  teeth  and  plate.  By  using  single  plain 


AND  HAND-BOOK. 


31 


teeth,  and  pink  rubber  attachments,  the  best  results 
can  be  attained,  next  to  continuous-gum. 

For  partial  lower  on  gold,  this  method  is  the  best, 
for  the  reasons  mentioned,  and  also  because  there  is 
such  a  tendency  of  the  process  to  give  way,  in  these 
cases,  that  it  is  necessary,  from  time  to  time,  to  re¬ 
move  the  teeth  and  set  them  higher,  and  this,  of 
course,  is  easily  done,  if  the  rubber  attachment  is 
used. 

Sometimes  partial  uppers  may  be  constructed  in 
the  same  manner,  especially  when  all  the  back  teeth 
are  replaced. 

The  method  of  attaching  is  to  invest  the  case,  as  if 
it  were  to  be  a  rubber  plate;  then  platina  loops 

at  intervals  on  the  plate ;  the  loops  may  be  -jig-  inch 
wide,  4  inch  long,  soldering  the  ends,  or  soldering  the 
middle  with  the  ends  turned  up.  In  an  upper  case 
put  lour  such  near  the  upper  edge  and  four  on  the 
ridge. 

After  soldering  on  the  loops,  place  the  flasks  to¬ 
gether,  and  see  that  none  of  the  teeth  come  in  contact 
with  the  loops  so  as  to  prevent  closure  of  flask. 

Another  method  is  to  spur  the  surface  with  a  sharp 
instrument;  this,  however,  cannot  always  be  relied 
on,  but  deep  spurs  in  the  cast  metal  plate  are  suffi¬ 
cient. 


32 


STUDENT  S  MANUAL 


CHAPTER  XIV. 


RELATIVE  VALUE  OF  THE  VARIOUS  MATERIALS  FOR 


PLATES 


OR  full  upper  sets,  continuous-gum  stands  pre- 


f  I  eminently  the  most  perfect,  in  all  respects,  of 
anything  ever  devised,  provided  it  is  made  as  it 
ought  to  be,  and  full  advantage  taken  of  its  capabili¬ 
ties.  It  most  nearly  resembles  nature,  not  only  in 
the  arrangement  of  the  teeth,  but  in  the  disposal  of 
the  gum  and  imitation  of  the  palate ;  it  is  the  most 
cleanly,  and  the  materials  are  in  no  way  objection¬ 
able  in  ,  the  mouth  ;  it  is  generally  the  strongest. 
More  than  thirty  years’  use  has  demonstrated  the 
truth  of  these  statements. 

Next  in  value  for  full  u'pper  and  in  nearly  all  par¬ 
tial  cases  is  gold.  This  has  been  used  from  the  earli¬ 
est  history  of  artificial  dentures,  and  has  been  fully 
tested. 

Next  in  order  for  full  uppers  may  be  mentioned 
platina,  with  rubber  attachments. 

Y or  partial  uppers  some  use  platina;  but  if  it  is 
pure  it  is  too  soft  for  the  purpose ;  it  niay,  however, 
be  alloyed  with  iridium. 

For  partial  lower  gold  is  the  best,  Avith  exceptional 
cases,  when  rubber  (the  black  or  the  maroon)  is  per¬ 
haps  better. 


AND  HAND-BOOK. 


33 


For  full  lower  sets,  where  the  gums  show,  which  is 
rare,  continuous-gum  should  be  used.  However,  in 
many  cases,  nothing  is  better  than  the  cast  metal 
plates,  with  rubber  attachments,  using  Watts’, 
Weston’s,  or  Reese’s  metal. 

Aluminum  is  used  to  some  extent,  but  is  objection¬ 
able  for  several  reasons.  If  the  plate  should  crack 
from  any  cause,  there  is  no  solder  suitable  for  the 
mouth  with  which  to  repair  ;  often  there  are  iron 
spots  in  it,  which  rust  through,  making  holes.  Re¬ 
cently,  however,  a  method  of  casting  these  plates  has 
been  devised,  which  promises  good  results. 

Next  in  order  is  rubber,  used  the  world  over  more 
than  any  other  material.  But  while  thus  used,  it  is 
open  to  serious  objections,  doing,  in  many  cases,  much 
harm  to  the  mouth;  a  subject  it  is  not  necessary  to 
discuss  here. 

It  is  not,  however,  an  unmixed  evil ;  it  enables 
many  people  to  wear  artificial  teeth  who  would  other¬ 
wise  be  unable  to  afibrd  them;  then  for  temporary 
work  it  answers  every  purpose ;  in  some  cases  for 
partial  lower  it  is  well  to  use  it. 

The  last  on  the  list,  celluloid,  is  the  least  in  value ; 
having  given  it  a  thorough  trial  for  six  years,  I  was 
compelled  to  abandon  it.  I  could  not  recommend  it 
to  my  patients  longer.  The  objections  to  it  are  those 
pertaining  to  rubber,  besides  being  more  uncleanly, 
2 


34 


student’s  manual 


absorbing  the  secretions.  It  is  difficult  to  repair,  and 
is  injured  in  appearance  by  the  process. 

There  is  still  another  material,  the  porcelain  plate. 
But  to  make  this  requires  long  practice,  and  even 
then  it  is  impossible  to  secure  all  the  results  necessary 
for  a  perfect  artistic  denture.  When  done  it  is  always 
difficult  to  repair,  and  sometimes  impossible.  I  do 
not,  however,  condemn  it. 

COMBINATION  WORK. 

There  is  but  one  kind  of  “  combination  work  ”  that 
is  advisable,  and  that  is  metal  plates  and  rubber  at¬ 
tachments. 

The  combination  of  continuous-gum  on  a  rubber 
base  was  made  quite  extensively  twenty-five  years 
ago,  and,  as  might  have  been  expected,  was  aban¬ 
doned.  It,  however,  came  to  light  again  across  the 
Atlantic  a  few  years  since. 

The  objection  to  it  is  the  difficulty  of  repair.  If  a 
tooth  is  broken,  the  continuous-gum  portion  must  be 
removed  and  repaired,  and  a  new  rubber  plate  made, 
involving  too  much  expense  for  the  replacement  of  a 
tooth.  The  same  objection  holds  good  in  continuous- 
gum  and  cast  metal  plates. 

The  combination  of  rubber  and  celluloid  is  a 
difficult  kind  of  work  to  make,  for  which  a  good  price 
should  be  charged,  and  then  the  price  charged  would 
have  paid  for  a  metal  plate,  which  would  have  been 
far  preferable. 


AND  HAND-BOOK. 


35 


The  combination  of  celluloid  and  gold  is  objection¬ 


able,  for  the  reasons  that  apply  to  the  celluloid  alone, 
and  also  that  the  celluloid  does  not  adhere  to  the 
plate,  and  in  case  of  repair  is  just  about  ruined. 


CHAPTER  XV. 


CONTINUOUS  -  GUM. 


HIS  is  the  most  difficult  to  make,  and  yet  the 


4  most  perfect  when  completed.  It  has  stood  the 
test  of  time,  and  remains  to-day  unparalleled  as  an 
artificial  denture.  I  do  not  see  how  there  can  be 
anything  superior  to  it,  at  least  in  its  adaptation, 
where  a  porcelain  gum  is  an  absolute  necessity,  but 
which  must  be  very  high,  and  very  thin,  with  no 
seams. 

There  cannot  be  too  much  care  bestowed  on  its 
construction,  and  it  amply  repays  the  careful  operator 
who  avails  himself  of  all  its  possibilities,  for  with  this 
work  the  shape  of  the  teeth  can  be  modified  by 
grinding,  or  building  on  to,  and  when  the  work  is 
finished  the  teeth  when  ground,  are  re-enameled. 

The  plate  should  be  swaged  the  same  as  for  gold, 
using  the  best  French  plate,  gauge  28.  After  fitting, 


.36 


student’s  manual 


and  articulating  bite  secured,  place  in  the  articulator 
and  remove  the  wax. 

With  lead  make  a  pattern  about  i  inch  wide,  cov¬ 
ering  the  entire  posterior  of  the  plate,  and  around 
the  corners.  This  is  for  a  “  doubler,”  and  should  be 
gauge  30.  First  swaging  in  the  dies,  fit  with  the 
burnisher,  and  turn  up  the  inner  edge  slightly  to  the 
top  of  the  tuberosity;  clamp  in  the  center,  after 
putting  in  a  little  borax  ;  solder  (always  using  pure 
gold,  as  alloyed  gold  would  discolor  the  gum  in 
baking)  for  about  ^  inch;  removing  the  clamps,  re¬ 
place  on  the  model,  and  burnish  again  closely,  and 
clamping,  solder  still  farther,  and  so  continue,  by  de¬ 
grees. 

Take  round  wire,  gauge  18  and  roll  to  gauge  21. 
File  one  edge  flat,  and  beginning  where  the  inner 
edge  of  the  doubler  is  turned  up,  fit  the  wire  with 
pliers  for  the  distance  of  IJ  inches,  clamp  and  solder 
only  i  inch ;  then  place  on  the  model,  and  fit  closely, 
a  short  distance  each  way,  and  solder  again,  and  so  on 
till  it  is  all  attached. 

The  teeth  being  arranged,  insert  in  equal  parts 
plaster  and  asbestos,  leaving  it  about  1  inch  thick 
underneath  and  all  around. 

When  hard,  warm  slightly  and  remove  the  wax, 
finally  dashing  boiling  water  into  it,  so  as  to  thor¬ 
oughly  cleanse  of  wax. 

Turning  up  the  pins,  make  three  patterns,  one  each 


AND  HAND-BOOK. 


37 


covering  the  molars,  bicuspids,  and  cuspids,  with  a 
foot-piece  inch  wide  resting  on  the  plate  ;  and  one 
piece  covering  the  six  front  teeth.  Use  the  backings 
same  thickness  of  the  plate ;  cut  the  edges  for  foot 
pieces  in  slits,  the  width  of  foot-piece,  and  turn  at 
right-angles,  and  with  an  instrument  (I  use  a  worn- 
out  scraper)  press  into  place,  under  the  pins.  The 
front  piece,  of  course,  will  lap  over  the  side  pieces, 
on  the  cuspids.  Have  the  pure  gold  rolled  very  thin, 
cut  in  small  pieces,  and  lay  underneath  the  foot-piece, 
and  a  piece  under  each  pin  as  it  is  turned  down, 
pressing  the  backing  snugly  to  the  plate ;  use  no 
borax. 

I  prefer  soldering  in  the  furnace,  the  first  thing 
after  the  fire  is  made.  It  can  be  done,  however,  with 
a  bellows  blow-pipe. 

After  cooling,  remove  the  investment,  saving  the 
base ;  wash  thoroughly,  and  there  is  no  need  of  boil¬ 
ing  in  acid.  Place  on  the  model,  and  press  into 
place  ;  see  by  the  articulator  if  the  position  of  any  of 
the  teeth  has  been  changed,  and  if  so,  correct. 

The  only  instrument  needed  for  applying  the  body 
as  used  is  a  wax-knife,  straight  and  pointed  at  one 
end,  and  slightly  curved  and  pointed  at  the  other. 
(Fig.  8.) 


Figure  8. 


38 


student’s  manual 


In  addition  to  this  there  is  required  a  quill  tooth¬ 
pick,  camel’s-hair  brush,  a  stiff  dry  brush,  a  set  of 
boxes,  setting  one  into  the  other  (used  by  artists),  a 
spatula,  a  small  cloth  for  absorbing,  and  a  small  glass 
of  water. 

The  materials,  body  and  gum,  are  ready  prepared, 
and  sold  at  the  dental  depots.  I  have  always  used 
that  made  by  S.  L.  Close. 

Apply  the  body,  which  has  been  moistened  so  as  to 
be  quite  thin,  with  the  flat  end  of  the  instrument  to 
the  outside ;  beginning  at  one  end,  work  it  thoroughly 
under  and  around  the  teeth,  by  jarring  ;  then  absorb¬ 
ing  with  the  cloth,  apply  more,  after  having  thickened 
it  somewhat ;  continue  this  process,  jarring  and  ab¬ 
sorbing,  then  pressing  hard ;  when  built  up  suffi¬ 
ciently,  dry  partially  over  the  gas  or  lamp,  contour¬ 
ing  the  gums  and  trimming  around  the  necks  of  the 
teeth.  Then  apply  to  the  palatal  surface  in  the  same 
manner  with  the  curved  end  of  the  instrument,  but 
thin  ;  brush  all  particles  from  the  teeth  or  plate ;  set 
on  the  base  which  has  been  saved  from  the  invest¬ 
ment,  place  on  a  slide  and  run  into  the  furnace  gradu¬ 
ally  on  a  sheet-iron  shelf  attached  to  the  furnace,  occu¬ 
pying  perhaps  half  an  hour,  the  heat  meantime  com¬ 
ing  up,  so  that  when  the  case  is  in  the  furnace  and 
the  muffle  closed,  there  is  a  baking  heat.  The  proper 
amount  of  heat  must  be  judged  by  the  appearance  of 
the  body,  it  having  a  glossy  look ;  place  in  a  cooling 


AND  HAND-BOOK. 


39 


muffle  and  close,  remaining  till  cool.  Care  of  course, 
must  be  taken  not  to  over-hake.  The  baking  is  not 
easily  learned  except  through  personal  instruction, 
and  must  be  closely  watched. 

It  will  be  found  that  the  body  has  shrunk,  and  left 
crevices,  which  must  be  filled  up  thoroughly,  and  the 
surface  built  up  to  the  proper  contour  again,  and  at 
this  stage  the  rugae  may  be  formed.  The  case  is  again 
run  into  the  muffle  slowly,  as  before,  and  baked. 
After  cooling,  the  gum  enamel  is  applied.  This  is 
done  with  the  same  instrument  as  the  body,  but  care 
is  required  to  put  on  a  uniform  coat,  with  proper 
shadings  ;  and  unless  properly  done  it  is  liable  to  curl 
up  from  the  body.  It  is  baked  the  same  as  the  body 
and  with  the  same  test. 

After  cooling,  file  the  binding  even  with  the  enamel, 
rounding  the  edge  of  plate  and  binding ;  file  the 
doubler  wherever  it  can  be  reached,  and  use  a  small 
fine  corundum  over  its  whole  surface.  Then  finish 
with  pumice  and  pine  stick  and  polishing  brushes. 
In  making  a  lower  set,  do  not  put  on  a  wire,  nor 
turn  the  edge,  but  double  the  edge  k  inch  wide  all 
around,  and  let  the  material  extend  to  the  edge. 

Repairing  is  easily  done,  with  a  little  experience. 
First  invest  the  entire  case  I  inch  thick  in  asbestos 
and  plaster,  and  place  in  the  back  of  the  muffle  before 
lighting  the  fire,  allowing  the  heat  to  come  up  slowly, 
and  the  case  to  remain  till  red ;  cool,  and  remove  in- 


40 


student’s  manual 


vestment,  saving  the  base.  Grind  out  the  remains  of 
tooth  or  teeth  to  be  replaced,  as  also  some  of '  the 
gum,  outside  and  inside ;  select  the  teeth  (rubber 
teeth  will  do),  and  fit  them  to  their  places.  If  there 
is  but  one  in  a  place,  it  can  be  held  there  with  the  body 
(which  should  be  of  a  lower  fusing  quality),  applied 
carefully  and  dried.  If  there  are  several  teeth, 
arrange  with  a  little  wax,  and  then  over  the  ends,  and 
also  on  one  or  two  adjoining  teeth,  place  a  thin  coat¬ 
ing  of  plaster  and  asbestos ;  remove  all  wax,  and  pack 
the  body  around,  quite  thin  at  first,  and  run  the  case 
into  the  muffle  somewhat  more  slowly  than  a  new  case. 
It  will  not  require  as  much  heat.  After  cooling,  place 
gum  where  needed,  and  bake. 

Sometimes  the  grinding  surfaces  of  the  molars  and 
bicuspids  appear  rough  after  baking ;  it  is  from  the 
presence  of  lime,  coming  from  the  secretions  of  the 
mouth ;  smooth  by  the  use  of  sandpaper. 

If  “  blisters  ”  appear,  grind  into  them,  and  fill  with 
repairing  body,  and  enamel  over  it." 

For  furnace,  both  the  coke,  and  gas  and  hydro¬ 
carbon”  are  being  used.  For  some  reasons  I  prefer 
and  use  the  coke  furnace.  I  like  a  large-sized  muffle  ; 
it  is  more  convenient  to  work  in.  I  have  always  used 
the  large-sized  Philadelphia  furnace,  taking  a  14-inch 
muffle.  I  arrange  the  bars  so  as  to  dispense  with  the 
bottom,  and  pull  the  bars  to  drop  the  ashes.  The 
furnace  should  be  arranged  with  a  shelf  in  front  of 


AND  HAND-BOOK. 


41 


the  muffle,  on  which  to  place  the  work  for  slow  en¬ 
trance  into  it.  The  muffle  should  be  luted  with  fire¬ 
clay  only  at  the  front,  leaving  the  rear  free,  as  there 
will  be  less  danger  of  its  cracking  across  the  middle 
from  shrinkage  in  a  high  heat. 

The  clinkers  should,  from  time  to  time,  be  removed 
from  the  sides  of  the  furnace  with  a  cold-chisel,  strik¬ 
ing  sudden  blows,  so  as  not  to  injure  the  lining. 

Tees’  Lilliput  Furnace  I  have  used  often  in  demon¬ 
strating.  It  works  nicely;  my  principal  objection  to 
it  is  that  the  muffles  are  small  and  thin. 

There  is  a  hydro-carbon  furnace,  made  by  Hoskins, 
Chicago,  which  does  good  work :  the  heating  arrange¬ 
ment  may  also  be  used  for  a  melting  furnace,  for  re¬ 
fining  gold,  etc. 

The  Verrier  Gas  Furnace  is  very  objectionable  for 
two  reasons — its  constant  liability  to  “gas ’’the  work, 
and  the  lilliputian  dimensions  of  the  muffle ;  some  sets 
could  not  be  put  into  it. 

The  most  perfect  gas  furnace  is  C.  H.  Land’s,  of 
Detroit.  He  claims  there  is  no  liability  to  “  gasing  ” 
in  its  use.  (Send  for  illustration  and  full  descriptive 
circulars  to  Dr.  Land,  or  to  Welch  Dental  Co.,  Phila.) 

Any  one  intending  to  undertake  the  construction  of 
continuous-gum  work  had  better  take  instructions  of 
some  competent  dentist  who  has  had  experience  in 
the  work,  as  there  are  many  little  details  which  can 
only  be  learned  in  this  way. 


42 


student’s  manual 

CHAPTER  XVI. 


CAST  METAL  PLATES. 

"I^JOR  full  lower  plates  these  are  generally  prefera- 
*  ble,  first  because  of  the  weight,  Avhich  is  a 
valuable  adjunct  of  lower  sets.  Then  we  have  metal 
in  contact  with  the  membrane,  which  is  an  advantage 
over  rubber,  and  being  a  non-shrinking  metal  (tin 
and  bismuth)  cast  on  a  non-shrinking  model  (plaster 
and  pumice,  or  sand),  furnishes  a  more  perfect  fit 
than  by  swaging,  and  as  alteration  of  the  margins  of 
lower  plates  is  often  necessary,  we  are  able  to  do  it 
without  injuring  the  appearance  of  the  work,  as  in 
gold  or  continuous-gum. 

The  process  is  as  follows :  Fill  the  impression  with 
plaster  and  pumice,  or  marble  dust,  equal  parts ;  re¬ 
move  the  impression  with  care,  as  it  is  not  as  strong 
as  pure  plaster ;  form  a  wax  plate,  and  double  the 
edge  i  inch  wide,  which  will  have  the  appearance, 
when  finished,  of  a  “rim;”  invest  the  model  in  Watts’ 
or  Weston’s  flasks,  using  equal  parts  plaster  and  pum¬ 
ice  or  marble  dust ;  when  hard,  warm  slightly  and 
remove  the  wax.  Now  cut  gates  in  the  plaster,  about 
inch  diameter,  from  the  extreme  point  of  each  heel, 
opening  into  the  flask  gates  ;  apply  heat  gradually 
till  all  moisture  has  disappeared,  evidence  of  which 


AND  HAND-BOOK. 


43 


can  be  had  by  holding  a  hand-mirror  over  the  plas¬ 
ter.  Then  close  the  flasks,  apply  the  clamp  and  pour 
the  metal  from  an  iron  spoon.  When  cool,  finish 
with  coarse  file  and  sand-paper.  Now  spur  the  sur¬ 
face  with  a  graver  quite  deeply.  Arrange  the  teeth 
as  in  a  rubber  set,  and]  attach  with  pink  rubber  and 
finish. 


CHAPTER  XVII 


VULCANIZED  RUBBER. 


RRANGE  on  the  plaster  cast  a  wax  plate, — or 


^  wax  and  gutta-percha  plate  is  preferable;  ar¬ 
range  a  rim  of  wax  on  it,  and  get  a  “  bite,”  to  show 
the  impression  of  the  loAver  teeth  and  relative  position 
of  the  jaws. 

If  a  full  upper  and  lower,  arrange  the  lower  wax 
and  trim  by  the  mouth  to  the  right  length ;  then 
place  the  upper  and  obtain  a  closure,  and  while  in 
position  make  several  lines  in  the  wax ;  remove  and 
trim  and  replace  to  see  if  the  closure  is  the  same 
each  time.  It  is  not  necessary  to  attempt  to  secure 
the  proper  fullness  and  length  in  the  wax ;  this  will 
have  to  be  done  when  arranging  the  teeth,  with  the 


44 


student’s  manual 


patient  in  the  chair,  whether  full  or  partial  cases, 
as  it  is  only  by  the  mouth  that  the  proper  arrange¬ 
ment  and  expression  can  be  secured. 

Place  the  cast  and  bite  in  an  articulator,  to  retain 
the  relative  position  of  the  jaws,  and  aid  in  arranging 
the  teeth. 

After  arranging  the  teeth,  form  the  wax  for  the 
gum,  so  as  to  restore  contour  of  features,  trying  in 
the  mouth  till  patient  and  dentist  are  satisfied  with 
the  result. 

Now  invest  in  the  flasks.  If  it  is  a  full  case,  in¬ 
vest  to  the  margin  of  the  wax ;  smooth  the  surface, 
shellac,  and  oil ;  place  the  other  half  of  flask  in  place, 
and  before  turning  the  plaster  in,  with  a  knife  spread 
some  over  the  surfaces  of  the  teeth,  so  as  to  be  sure 
it  will  fill  all  spaces  between,  then  turn  in  a  portion 
of  the  remainder,  and  jar,  so  as  to  be  rid  of  air-bub¬ 
bles.  To  remove  the  wax,  place  in  pan  of  cold  water 
over  the  gas,  and  as  soon  as  it  begins  to  boil  remove 
and  separate,  and  it  will  be  found,  usually,  that  the 
wax  can  be  easily  removed.  Then  to  clean  thorough¬ 
ly,  dash  hot  water  on  it;  cut  narrow  gates  J  inch 
apart  all  around,  and  scrape  the  entire  surface 
slightly  to  insure  closure  of  flasks. 

To  pack,  place  the  pieces  of  rubber  on  a  plate  of 
tin  or  zinc  placed  over  a  pan  of  hot  water.  If  you 
would  be  specially  accurate  of  the  amount  of  rubber, 
measure  as  follows :  Have  a  glass  test-tube,  or  some 


AND  HAND-BOOK. 


45 


similar  utensil ;  save  the  wax,  roll  it  up  and  put  it 
in  the  tube,  filling  with  water  carefully ;  remove  the 
wax  and  in  its  place  put  the  rubber,  till  the  water  is 
at  the  top  again,  and  then  add  a  little  for  excess. 

Observe,  when  waxing  up,  whether  one  side  re¬ 
quires  more  material  than  another,  and  bear  this  in 
mind  in  packing.  Pack  small  pieces  behind  the  teeth, 
and  then  use  strips,  and  one  piece  sufficient  in  size  to 
cover  the  palate. 

For  rubber,  the  red,  colored  with  bisulphide  of  mer¬ 
cury,  is  objectionable ;  serious  results  have  sometimes 
followed  its  use.  The  black  and  the  maroon  are 
free  from  deleterious  substances.  For  the  surface  of 
the  gums  use  the  pink.  The  color  of  this  is  improved 
by  bleaching  with  alcohol  in  a  glass  jar  exposed  to 
the  sun  for  half  an  hour  or  more. 

The  palatal  surface  should  be  covered  with  tin  foil ; 
cut  a  piece  the  proper  size,  and  with  a  cloth,  or  tis¬ 
sue  paper,  rub  it  to  the  cast,  and  it  will  adhere  suffi¬ 
ciently.  Then  slightly  coat  with  soa23,  to  prevent  its 
adhering  to  the  rubber  when  vulcanized. 

Put  the  flasks  together,  and  place  in  the  press,  im¬ 
mersing  both  in  the  hot  water ;  bring  gradually  to¬ 
gether.  If  you  have  any  doubts  of  a  lack  of  rubber, 
open  and  examine,  for,  though  there  may  be  enough, 
it  may  be  unequally  distributed. 

Instead  of  using  the  bolts  to  hold  the  flask,  the 
“  spring-clamp  ”  is  preferable. 


46 


student’s  manual 


As  to  vulcanizers,  you  must  take  your  choice. 
Some  are  more  easily  adjusted  and  handled  than 
others.  A  vulcanizer  arranged  with  a  steam  gauge  is 
more  reliable  than  one  with  thermometer  attached. 

If  the  rubber  is  very  thick,  the  heat  should  be  ap¬ 
plied  more  slowly  than  with  thin  rubber,  to  avoid  its 
becoming  porous.  The  black  rubber  requires  lower 
temperature  and  longer  time.  In  fact,  in  this  way 
all  rubber  is  stronger,  so  that  instead  of  vulcanizing 
at  320°  for  45  or  55  minutes,  280°  to  300°  for  two 
hours  produces  tougher  rubber. 

On  opening  the  flasks,  try  the  rubber  by  breaking 
off  a  gate,  to  see  if  it  is  hard  enough. 

With  coarse  file,  shape  the  margins  and  surface  of 
gums ;  then  use  the  large  bur  for  the  lingual  surface, 
using  the  calipers  to  avoid  making  it  too  thin,  yet 
give  the  patient  all  the  space  possible  for  the  tongue, 
without  sacrificing  strength.  With  thin,  sharp  chisel 
trim  around  the  necks  of  the  teeth,  and  with  small, 
sharp  points  between.  Use  the  round  scraper  for  the 
surface.  Sand-paper  (No.  0  or  00)  thoroughly,  and 
finish  with  pumice,  either  with  a  pine  stick  in  the 
hand  or  felt  cone,  or  both,  and  finally  with  small,  soft 
brush  wheels. 

A  partial  case,  where  there  is  no  rubber  outside 
the  gums,  should  be  invested  in  the  deep  part  of  the 
flask,  covering  the  teeth  entirely. 


AND  HAND-BOOK. 


47 


CHAPTER  XVIII. 


CELLULOID. 

tHE  process  for  celluloid  is  similar  to  that  for 
rubber,  but  requiring  a  different  flask.  Instead 
of  packing  a  soft  material  in  the  molds,  as  contained 
in  the  flasks,  to  be  hardened,  a  hard  material  is  placed 
between,  to  be  softened  and  pressed  into  place. 

The  celluloid  is  prepared  in  blanks,  of  various  sizes 
and  shapes.  When  the  case  is  ready  for  the  blank, 
it  is  placed  between,  sometimes  altering  by  filing,  or 
heating  in  boiling  water  and  bending,  so  as  to  bring 
into  better  shape  for  the  flasks. 

There  are  two  methods  of  applying  heat,  dry  and 
steam.  There  are  various  apjDliances  for  this  purpose. 
The  latest  and  most  perfect  is  the  New  Mode  Heater, 
where,  though  steam  is  used,  the  case  is  in  a  dry  air 
chamber. 

The  cheaper  appliances  for  this  work  are  not  de¬ 
sirable,  and  have  long  since  been  abandoned  by  most 
of  those  who  have  used  them.  I  have  given  them 
a  six-years  thorough  trial. 

Finish  the  same  as  rubber.  It  should  never  be 
allowed  to  remain  out  of  the  mouth  without  being 
placed  in  water,  as  it  has  a  tendency  to  warp. 


48 


student’s  manual 


KEP  AIRING. 


GOLD  OR  SILVER. 

) REMOVE  the  remains  of  the  broken  tooth,  and, 
i  with  plate  nippers  and  file,  remove  the  backing. 
Select  a  tooth,  and  wax  it  into  place ;  insert  in  plaster 
and  sand,  or  marble  dust,  and  put  on  the  backing. 

These  repair  cases  should  be  heated  slowly,  taking 
an  hour  for  the  purpose,  then  solder.  Cool  off  slowly, 
and  it  will  be  a  rare  occurrence  that  a  tooth  cracks. 
This  has  been  my  exjierience. 

If  the  plate  has  cracked  and  spread,  let  it  remain 
in  that  condition,  as  it  has  followed  a  change  in  the 
gums.  Place  borax  on  the  under  side,  and  lay  a 
piece  of  wet  tissue  paper  over  the  crack  on  that  side, 
so  the  plaster  will  not  get  into  the  crack.  Scrape  the 
surface  of  the  plate ;  invest  and  fit  a  small  piece  of 
plate  over  the  crack  ;  lay  the  solder  in  small  pieces 
along  the  sides  ;  heat  and  solder.  If  your  solder  is 
right  and  you  give  it  proper  heat,  it  will  not  only 
flow  under  the  piece  of  plate,  but  also  into  the  crack. 

RUBBER. 

Remove  the  broken  tooth,  and  file  away  the  rub¬ 
ber  back  of  it ;  select  a  tooth  that  will  go  into  the 
impression  of  the  neck  of  the  former  tooth,  and  wax 
into  place ;  insert  in  the  deep  half  of  the  flask ;  re¬ 
move  the  wax,  scrape  the  surface  of  the  rubber,  and 


AND  HAND-BOOK. 


49 


apply  a  little  of  the  solution  of  rubber  in  chloro¬ 
form,  and  pack ;  no  holes  nor  dovetails  are  ever 
needed. 

If  the  plate  is  cracked,  cut  away  the  length  of  the 
break,  from  each  side,  i  inch,  and  nearly  the  thick¬ 
ness  of  the  plate  at  the  break.  If  the  break  has  ex¬ 
tended  to  the  outer  edge,  under  the  teeth,  remove  one 
of  the  teeth,  cut  away  a  portion  of  the  break,  wax 
the  tooth  into  place,  and  wax  over  the  break,  invest, 
and  wash  out  all  the  wax,  and,  if  necessary,  remove 
the  tooth,  and  pack  the  rubber  back  of  it,  then  re¬ 
place  and  pack  elsewhere,  and  vulcanize. 

In  repairing  a  partial  lower,  carefully  place  the 
fractured  ends  together  and  wax  into  place ;  insert 
and  cut  away  the  rubber  for  a  space  of  i  inch  each 
side  of  the  fracture,  and  at  the  fracture  to  its  full 
depth ;  pack  as  above. 

CELLULOID. 

Prepare  as  in  rubber,  and  after  removing  the  wax, 
scrape  the  surface,  apply  camphor,  and  place  a  piece 
of  celluloid,  wet  with  the  camphor,  where  needed,  and 
put  into  the  press ;  apply  a  strong  heat,  and  press 
into  place. 


50 


student’s  manual 


CHAPTER  XIX. 


SELECTION  AND  AREANGEMENT  OF  TEETH. 

X  no  department  of  dental  practice  is  more  skill, 
judgment,  and  experience  needed  than  in  this ; 
and  in  none  is  there  so  little  manifest,  if  we  judge 
from  the  average  artificial  dentures  in  wear,  especial¬ 
ly  full  sets. 

Dr.  W.  W.  Allport,  of  Chicago,  well  expressed  it 
in  an  address  before  the  Boston  Academy  of  Dental 
Science : 

“He  who  has  but  moderate  ideas  of  symmetry, 
harmony  of  expression,  and  color,  is  constantly  pained 
by  the  lack  of  that  artistic  selection  and  arrangement 
of  artificial  teeth  which  serve  to  restore  to  the  face 
the  shape  and  expression  left  on  it  by  the  Creator, 
the  absence  of  which  in  artificial  dentures  stamps 
him,  who  should  be  an  artist,  an  artisan,  as  a  mere  me¬ 
chanic — a  liheler  of  the  soul — a  deformer  of  the  human 
face  divine.  That  mechanical  dentistry  should  have 
very  largely  fallen  into  the  hands  of  this  inferior 
class  of  practitioners  will  hardly  be  wondered  at  by 
those  who  have  watched  the  history  of  this  branch  of 
the  practice.  For  so  simple  are  the  modes  of  attain¬ 
ing  tolerable  mechanical  results,  with  the  methods 
now  usually  employed  in  this  department,  by  the  use 


AND  HAND-BOOK. 


51 


of  rubber  plates  and  ‘  gum  sections/  that  one  possess¬ 
ing  a  high  order  of  appropriate  talent  is  seldom  found 
devoting  much  time  to  it.” 

It  is  difficult  to  give  oral  or  written  instruction  on 
this  subject ;  it  requires  the  clinic,  often  repeated.  As 
we  are  at  work  on  the  natural  teeth,  we  should  study 
the  subject  from  that  standpoint. 

The  indiscriminate  use  of  “  gum  sections  ”  is  largely 
responsible  for  many  failures ;  for  it  is  impossible  to 
secure  proper  results,  in  all  respects,  where  they  are 
used.  Their  appearance  is  sometimes  an  outrage  on 
the  human  face. 

I  long  ago  ceased  to  use  them,  using  instead  plain 
teeth  and  pink  rubber  gums.  The  question  is  asked 
by  dentists,  “  Suppose  your  patient  says  she  wants  a 
more  natural-looking  gum  ?  ”  I  tell  her  it  is  better 
to  sacrifice  somewhat  on  the  color  of  the  gum  than  so 
much  in  other  respects,  by  the  use  of  gum  teeth.  I 
never  yet  have  had  to  change  the  teeth  in  such  cases. 

I  arrange  the  teeth  and  a  wax  gum,  and  tell  the 
patient  that  the  wax  will  be  replaced  with  a  gum, 
but  do  not  say  what  kind,  and  they  seldom  speak  of 
it  afterwards. 

If  there  is  prominence  of  the  upper  jaw  and  short 
lip,  the  worst  class  of  cases  to  deal  with,  the  gum  teeth 
are  utterly  out  of  place,  because  while  a  porcelain 
gum  is  a  necessity,  it  must  be  very  thin,  high,  and 
seamless.  In  these  the  continuous-gum  j^rocess  is  the 


52 


student’s  manual 


only  available  one,  as  by  it  a  thin  gum  can  be  se¬ 
cured  and  yet  be  strong,  because  it  is  baked  to  the 
plate. 

In  selecting  teeth,  if  there  are  teeth  remaining  in 
the  jaw,  there  is  little  difficulty,  because  it  is  only 
necessary  to  match,  in  shape  and  color,  these  natural 
teeth. 

Do  not  use  gum  teeth  unless  it  is  absolutely  neces¬ 
sary.  If  it  is,  look  for  teeth  with  the  gums  extending 
but  a  short  distance  below  the  neck  of  the  tooth,  as  the 
natural  gum  has  receded  and  needs  to  be  matched  in 
this  respect.  The  corners  of  the  gum  on  a  single 
tooth  should  be  rounded  and  ground,  to  match  nicely 
the  natural  gum.  Generally  there  is  not  room  for 
plate  behind  the  gum,  without  making  the  gum  too 
thin,  or  preventing  the  setting  of  the  gum  sufficiently 
far  back  to  match  on  to  the  natural  gum.  The  gum 
as  well  as  the  teeth  should  match  in  shade. 

'As  far  as  possible,  select  front  teeth  with  the  pins 
•  'perpendicular ;  occasionally  the  bicuspids  and  molars 
require  “  cross  ”  pins. 

In  partial  rubber  sets,  the  rubber  can  often  be  used 
for  gums,  and  when  possible,  it  is  better. 

If  the  bite  is  so  close  in  front  there  is  not  room  for 
the  thick  rubber  teeth,  select  a  plate  tooth,  and  solder 
a  backing,  with  a  foot-piece  that  can  be  enclosed  in 
the  rubber. 

If  the  bite  is  very  close  over  the  lower  posterior 


AND  HAND-BOOK. 


53 


teeth,  make  use  of  cuspids,  or  else  what  are  known  as 
“  crown  ’’  teeth,  instead  of  bicuspids  and  molars,  and 
have  the  lower  teeth  close  on  a  rubber  surface. 

In  case  of  a  gold  plate,  when  this  condition  of 
things  exists,  attach  the  teeth  with  rubber,  or  make  a 
shoulder  of  gold  to  bite  on. 

In  the  selection  of  teeth  for  full  upper  sets,  the 
lower  are  usually  a  guide  in  color  and  size.  I  say  in 
size,  in  this  way:  the  upper  teeth,  when  properly 
articulated,  should  be  so  arranged  that  the  cusp  of  the 
lower  cuspid  is  between  the  upper  lateral  and  cuspid ; 
so  that  upper  teeth  which  do  this  it  may  safely  be  as¬ 
sumed  are  the  size  of  the  natural  ones.  This  allows 
of  the  interlocking  of  the  bicuspids,  as  nature  arranges 
for.  If,  in  the  preparation  of  the  mouth,  there  should 
be  extracted  a  central  incisor,  be  sure  to  retain  it  as  a 
guide  in  the  selection  of  artificial  teeth.  The  patient 
will  sometimes  insist  that  you  have  selected  teeth 
larger  than  the  natural.  I  have  often  in  this  way 
shown  patients  that  I  have  selected  teeth  no  larger,- 
and  sometimes  a  trifie  narrow,  when  they  have  sup¬ 
posed  their  new  teeth  were  larger. 

There  is  a  great  tendency  to  use  small  and  white 
teeth,  which  often  give  an  insignificant  expression 
to  the  mouth,  the  patient  looking  as  though  wearing 
deciduous  teeth.  I  sometimes  remind  them  that  it  is 
time  they  had  shed  their  baby  teeth. 


54 


student’s  manual 

The  dentist  must  be  guided  by  the  general  appear¬ 
ance  of  the  natural  teeth.  The  study  of  physiognomy 
and  temperament  is  of  great  value  in  deciding  what 
to  do  when  all  the  natural  teeth  are  missing.  As  a 
guide,  I  have  prepared  the  following  table,  abbreviated 
from  the  elaborate  one  of  Dr.  J.  Foster  Flagg’s, 
which  will  be  found  serviceable.  Of  course  there  are 
variations  from  these,  as  there  are  combinations  of 
temperament. 


AND  HAND-BOOK 


55 


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56 


student’s  manual 


All  teeth  are  variably  yellow  at  the  neck  (some 
very  slightly).  They  become  darker  from  the  cuspids 
to  the  posterior.  The  cuspids  are  always  more  yellow 
than  the  incisors,  and  the  bicuspids  and  molars  darker 
still. 

This  rule,  however,  is  not  followed  by  the  manu¬ 
facturers,  but  the  dentist,  in  matching  partial  sets,  at 
least,  should  see  that  the  posterior  teeth  are  the  darker. 
Usually,  there  is  more  yellow  in  the  lower  than  in 
the  upper  teeth. 

It  is  not,  however,  always  possible  to  secure  just  the 
shade  required  from  the  stock  to  which  you  have 
access ;  neither  is  it  the  case  in  the  large  stocks,  for 
in  shades  there  seems  to  be  a  “  screw  loose  ”  some¬ 
where  in  the  manufacture  of  mineral  teeth.  This  is 
partly  because  so  many  dentists  are  indifferent,  or  do 
not  know  what  is  proper.  If  dentists  had  more  culti¬ 
vated  tastes  and  were  more  particular,  so  as  to  make 
an  imperative  demand  for  better  shaded  and  shaped 
teeth,  they  would  speedily  be  made. 

There  are  certain  general  directions  that  may  be 
given  for  the  arrangement  of  the  teeth. 

First,  in  length,  avoid  too  short  teeth,  especially  in 
full  upper  and  lower  sets  ;  they  should  be  in  propor¬ 
tion  to  the  length  of  the  face ;  they  should  neither  be 
so  long  as  to  give  the  lips  a  stretched  appearance,  nor 
so  short  as  to  be  hidden,  or  to  compress  the  lips,  as  in 
an  aged  look. 


AND  HAND-BOOK. 


57 


If  the  upper  lip  is  short,  the  natural  teeth  show 
much  more  than  when  it  is  long.  Some  persons  can 
scarcely  cover  the  natural  teeth ;  they  show  the  whole 
length  of  teeth  and  much  of  the  gum.  If  the  upper 
lip  is  very  long,  the  natural  teeth  do  not  show  at  all. 

The  lower  teeth  do  not  generally  show  as  much  as 
the  upper ;  seldom  are  the  gums  seen. 

Rarely  allow  a  drawn-m  appearance  to  the  upper 
teeth.  It  sometimes  occurs  in  the  natural  organs,  but 
is  a  deformity,  like  some  other  irregularities,  not  to 
be  followed.  The  teeth,  as  a  rule,  should  stand  per¬ 
pendicular,  avoiding  either  an  inward  or  an  outward 
slant.  Of  the  six  front  teeth,  the  cuspids  should 
generally  be  the  most  prominent,  especially  at  the 
neck.  The  bicuspids  should  drop  inside  a  trifle  of 
the  range  of  the  cuspids,  and  from  there  back  be 
nearly  on  a  straight  line. 

There  are  various  irregularities  of  the  natural 
teeth ;  such  as  over  or  under-lapping  of  the  laterals 
and  centrals.  If  it  is  a  pointed  jaw,  and  the  lower 
front  teeth  are  contracted,  the  centrals  should  be  the 
most  prominent,  and  the  laterals  droppmg  back  a 
little,  and  the  cuspids  still  more. 

If  the  arch  is  broad,  the  laterals  should  overlap,  if 
not  in  a  line  with  the  centrals.  We  should  set  the 
teeth  apart  in  some  mouths  where  there  is  plenty  of 
room,  and  close  or  even  lapping  when  there  is  a  small 
arch,  and  in  some  mouths  make  the  teeth  quite  irre- 


58 


student’s  manual 


gular,  if  it  is  a  person  of  large  build,  especially  if  his 
lower  teeth  are  crowded  and  irregular. 

Never  consider  it  necessary  to  make  the  teeth  abso¬ 
lutely  ugly,  to  look  natural. 

For  a  lady  of  regular  features,  irregularities,  except 
slight  ones,  are  to  be  avoided.  Nothing  more  than 
the  setting  apart,  or  slight  tipping  of  a  lateral,  is 
needed. 

It  is  the  upper  teeth  which  mainly  give  expression 
to  the  features,  therefore  they  should  have  our  chief 
attention.  Where  both  sets  are  being  inserted,  they 
should  always  be  arranged  together. 

In  the  arrangement  of  the  lower  teeth,  after  the 
length  is  decided  on,  the  width  of  the  six  anterior 
teeth  should  be  such  as  to  bring  them  within  the 
proper  compass  for  a  correct  articulation  ;  that  is,  so 
t\)iQ  point  of  the  lower  cuspid  comes  between  the  upper 
lateral  and  cuspid.  Then  there  is  no  difficulty  in 
securing  a  correct  apposition  of  the  bicuspids  and 
molars.  To  do  this,  it  is  usually  necessary  to 
crowd  the  lower  teeth,  unless  the  uppers  are  large. 
The  over-lapping  and  irregularity  of  the  lower  teeth 
are  generally  in  the  line  of  nature,  and  always  give 
a  natural  appearance. 

Of  all  places,  gum  sections  are  most  out  of  place 
on  the  lower  jaw.  The  necessity  of  setting  the  teeth 
sufficiently  in  over  the  ridge  makes  it  generally  im¬ 
possible  to  get  them  there  without  grinding  away  the 


AND  HAND  BOOK. 


59 


gum  too  much  ;  with  them  it  is  next  to  impossible  to 
give  the  proper  arrangement  of  the  teeth  so  as  to 
secure  a  correct  expression  and  articulation.  If  gum 
sections  are  used  on  the  upper  jaw,  they  should  at 
least  be  discarded  on  the  lower. 

The  utmost  stress  must  be  laid  on  the  correct  closure 
of  the  teeth.  There  are  more  failures  arising  from 
this  cause  than  from  misfits.  The  jaws  should  close 
so  as  not  to  disturb  the  position  of  the  plates,  other¬ 
wise  there  is  trouble.  It  should  be  borne  in  mind  that 
whenever  the  patient  swallows,  as  they  are  constantly 
doing,  without  thought  of  it,  the  jaws  close  tightly, 
and  this,  of  course,  displaces  the  plates  if  the  teeth 
are  not  properly  articulated. 

A  common  fault  is  the  interference  of  the  anterior 
teeth.  When  they  strike  before  the  posterior  teeth 
do,  the  upper  plate  is  crowded  forward  and  down 
from  the  rear. 

The  six  anterior  should  never  meet,  except  where 
mentioned  later.  When,  as  is  usually  the  case,  the 
upper  close  outside  the  lower,  they  should  drop  not 
more  than  3  inch  below  the  ends  of  the  lower,  and 
there  should  be  at  least  i  inch  space  horizontal 
between  them,  and  even  then,  in  time,  by  the  settling 
of  the  gums,  they  will  come  together,  and  need  grind¬ 
ing  to  prevent  strong  pressure. 

If  it  is  a  protruding  ^pwer  jaw,  let  the  upper  teeth 
be  arranged  over  the  ends,  but  not  meeting ;  the  back 


60 


student’s  manual 


teeth  being  long  enough  to  take  the  pressure  off  the 
front  teeth.  In  excessive  prominence  of  the  lower 
teeth,  arrange  the  ends  of  the  upper  teeth  inside 
of  the  lower,  as  nature  had  done ;  then  if  they  do 
meet  slightly,  the  pressure  will  be  favorable  to  the 
upper. 

The  posterior  upper  teeth  should  never  be  allowed 
to  drop  on  an  inclined  plane  from  the  cuspid  to  the 
molar.  The  expression  is  bad,  and  the  possible  ad" 
vantage  claimed  by  some  in  use,  is  not  sufficient  com¬ 
pensation. 

The  manner  in  which  the  surfaces  of  the  bicuspids 
meet  is  of  importance.  The  'posterior  side  or  slope  of 
the  lower  bicuspid  should  press  on  the  anterior  side 
of  the  upper.  The  lower  anterior  teeth  should  be  set 
well  in  over  the  ridge,  otherwise  there  is  undue  prom¬ 
inence  of  the  lower  lip. 

The  pressure  should  fall  mainly  on  the  bicuspids 
and  first  molars,  not  allowing  the  second  molars  to 
meet,  because  when  there  shall  be  a  closer  approxi¬ 
mation  of  the  jaws  by  the  settling  of  the  gums,  thes^ 
teeth  will  feel  the  pressure  excessively,  and  there  will 
be  irritation  of  the  membrane  and  crowding  forward 
of  the  plates ;  this  will  be  felt  specially  on  the  lo'wer 
jaw,  and  require  the  shortening  of  these  molars. 

If  there  are  wisdom  teeth  standing  alone  on  the 
lower  jaw,  they  are  usually  j^jiclined  forward,  so  the 
surface  is  often  at  an  angle  of  45°.  They  should 


AND  HAND-BOOK. 


61 


be  avoided  in  arranging  the  upper  teeth,  for  if  they 
meet  it  will  result  in  crowding  the  plate  forward,  and 
the  difficulty  will  constantly  increase. 

A  difficult  condition  of  things  is  met  when  a  full 
upper  set  is  inserted,  and  there  remains  on  the  lower 
jaw  the  six  anterior  teeth,  and  on  one  side  one,  or 
perhaps  two,  bicuspids,  and  nothing  on  the  other. 
Here  there  is  nothing  to  counterbalance  the  pressure 
on  these  bicuspids.  The  insertion  of  partial  lower 
would  be  of  no  value,  for  they  would  soon  yield  to 
pressure ;  but,  if  these  bicuspids  were  extracted,  and 
on  both  sides  were  artificial  teeth,  the  difficulty  w^ould 
be  removed ;  the  patient  would  have  a  good  mastica¬ 
ting  surface,  and  no  displacement  of  the  plate.  In 
such  instances  the  best  interests  of  the  patient  should 
be  consulted,  and  not  mere  sentiment  about  extract¬ 
ing  sound  teeth. 

If  all  the  teeth  remain  on  one  side  and  none  on  the 
other,  make  a  virtue  of  necessity,  as  there  is  so  much 
involved  in  the  sacrifice.  Build  a  biting  surface  for 
the  lower  cuspid ;  if  it  is  a  rubber  plate,  insert  a  small 
piece  of  a  tooth,  with  the  j)ins  in  it,  in  the  rubber 
back  of  the  upper  cuspid. 

The  articulation  of  teeth  is  sometimes  very  difficult. 
Great  care  must  be  exercised  that  there  is  no  one 
tooth  nor  one  side  meeting  before  the  other. 

When  the  lower  anterior  teeth  are  much  longer 
than  the  bicuspids,  shortening  of  them  is  always  de- 


62  student’s  manual 

sirable,  or  sometimes  building  up  these  bicuspids  or 
placing  crowns  on  them  is  essential.  If  this  is  not 
done,  make  the  upper  bicuspids  sufficiently  long  to 
throw  the  jaws  apart,  so  that  the  upper  will  not  close 
too  far  below  the  ends  of  the  lower.  If  the  surfaces 
of  the  bicuspids  are  inclined  planes,  grind,  if  possible, 
so  as  to  make  a  square  biting  surface. 

The  general  position  of  the  lower  posterior  teeth 
should  be  such  that  the  force  of  the  pressure  is  toward 
the  centre  of  the  upper  ridge,  and  not  outward.  It 
is  usually  more  difficult  to  j)roperly  arrange  the  lower 
set  than  the  upper. 

The  two  sets  should  always  be  arranged  together, 
then  finish  one  and  try  in,  and  correct  any  faults  aris¬ 
ing  from  the  two  sets  in  wax  arranged  at  once. 

The  arrangement  or  disposal  of  the  artificial  gum 
is  often  overlooked  ;  in  fact,  with  the  gum  sections  it 
is  not  possible  to  arrange  so  as  to  properly  restore 
the  contour  of  the  lips.  In  all  cases  the  fullest  and 
highest  point  should  be  over  the  cuspids ;  this  would 
often  relieve  the  undue  fullness  under  the  nose,  so 
common  in  most  dentures. 

In  95  per  cent,  of  mouths,  there  is  more  depression 
at  the  left  side  in  the  region  of  the  cuspids  than  at 
the  right,  so  that  the  teeth  need  to  be  extended  lower 
from  the  plate,  to  secure  a  proper  range  with  the 
lips ;  and  also  more  thickening  of  the  artificial  gum, 
to  restore  the  contour  of  the  lip. 


AND  HAND-BOOK. 


63 


TEMPORAEY  WORK. 

Patients  dislike  to  go  very  long  without  teeth,  and 
it  is  unnecessary.  Long  experience  has  satisfied  me 
that,  as  a  rule,  the  teeth  should  be  inserted  within  48 
hours  after  extraction,  taking  the  impression  as  soon 
as  the  bleeding  has  stopped,  and  before  the  gums  have 
swollen. 

When  the  front  teeth  or  their  remains  have  just 
been  removed,  I  make  use  of  the  socket  to  insert,  for 
a  short  distance,  the  neck  of  the  artificial  teeth,  giv¬ 
ing,  of  course,  a  natural  appearance  to  them. 

There  is  rarely  room  for  an  artificial  gum  in 
temporary  cases,  and  then  only  that  furnished  by  the 
rubber  plate  being  allowed  to  cover  the  alveolar  ridge. 

On  the  lower  jaw,  if  many  teeth  have  been  extract¬ 
ed,  it  is  better  to  wait  till  the  gums  are  healed ;  but  if 
the  patient  is  desirous  of  having  them  at  once,  make 
them ;  if  the  remains  of  the  front  teeth  have  just  been 
removed,  set,  as  in  the  upper,  the  necks  of  the  teeth 
into  the  sockets.  It  is  seldom  possible  to  cover  the 
outside  of  the  alveolar  ridge  with  the  plate,  without 
projecting  the  lip. 

Injury  comes  to  the  ridge  by  wearing  the  temporary 
plates  too  long.  It  causes  excessive  absorption  where 
it  presses  too  hard,  and  is  quite  annoying.  The  patient 
should  visit  the  dentist  occasionally  that  changes  may 
be  made  in  the  plate  or  grinding  surfaces  of  the  teeth 
as  the  gums  settle. 


64 


student’s  manual 


CHAPTER  XX. 


ADJUSTMENT  IN  THE  MOUTH. 

^(FTER  the  work  is  completed,  be  careful  to  adjust 
it  in  the  mouth  so  as  to  leave  as  favorable  an 
impression  as  possible. 

If  it  is  a  clasp  plate,  see  that  the  clasps  spring  into 
place  so  as  to  hold,  and  yet  not  be  injuriously  tight. 
See  that  the  teeth  are  articulated  in  partial  sets,  so 
that  the  pressure  is  thrown  on  the  natural  organs. 

In  adjusting  a  full  set,  the  greatest  care  must  be 
taken  to  see  that  the  articulation  is  correct.  Then 
say  to  the  patient,  “  If  you  find  the  plate  hurts  you, 
call  soon  and  have  the  excessive  pressure  relieved,  for 
it  is  not  necessary  to  suffer ;  relief  should  be  afforded 
at  once.”  It  is  advisable  to  see  the  patient  in  a  few 
days  to  be  sure  the  articulation  is  correct.  Too  much 
stress  cannot  be  laid  on  this  point. 

There  are  mouths  where  all  the  conditions  are 
favorable,  so  that  it  is  easy  to  secure  results  satisfac¬ 
tory  to  the  patient  as  well  as  to  yourself.  There  are 
mouths  where  all  the  conditions  are  unfavorable,  and 
after  the  dentist  has  done  all  that  care,  skill,  and  ex¬ 
perience  can  accomplish,  the  patient  will  complain, 
and  wonder  why  the  teeth  do  not  work  as  satisfactorily 
as  Neighbor  Blank’s.  It  is  often  because  the  condi¬ 
tions  of  the  mouth  are  entirely  different  or  unfavor- 


AND  HAND-BOOK. 


65 


able  to  the  best  results.  The  only  thing  is  to  impress 
the  importance  of  patience  and  constant  use  of  the 
teeth.  Time  and  perseverance  will  accomplish  won¬ 
ders. 

A  few  hints  may  be  given  on  the  use  of  artificial 
teeth,  as,  for  instance,  in  biting  an  apple ;  if  the 
teeth  are  used  as  the  natural  teeth  are,  they  are  liable 
to  be  thrown  down  from  behind.  The  new  teeth 
must  be  pressed  against  in  biting.  In  masticating,  if 
the  food  is  all  placed  on  one  side,  the  leverage  is  such 
that  the  plate  is  displaced ;  and  yet,  in  time,  the  pa¬ 
tient  will  learn  to  eat  on  one  side ;  but  at  first  divide, 
and  with  the  tongue  place  the  food  on  both  sides. 


‘6 


66 


student’s  manual 


EXTRACTS  OF  NOTES  ON  ORTHODONTIA,  WITH  A  NEW 
SA^STEM  BY  REGULATION  AND  RETENTION. 


EDWARD  H.  ANGLE,  D.D.S.,  MINNEAPOLIS. 

Professor  of  Dental  Anatomy  and  Instructor  in  Orthodontia  in  the  Den 
tal  Department  of  the  Minnesota  Hospital  College. 


Read  before  the  Ninth  International  Medical  Congress,  Dental  Section. 

inN  studying  the  conditions  by  which  we  may  best  ac- 
ijO  complish  the  movements  of  the  teeth,  we  may  sim¬ 
plify  the  process  if  we  remember  the  movements  in  the 
line  of  the  arch,  which  are  five :  forward,  backward,  in¬ 
ward,  outward,  and  partial  rotation.  These,  and  their 
slight  modifications,  with  the  exception  of  elongation 
and  depression,  which  are  rare,  are  all  we  are  called 
on  to  perform.  The  principles  governing  all  of  these 
movements  are  the  same.  So  that,  by  understanding 
the  principles  governing  one,  we  may  comprehend  all. 

In  applying  force  to  a  tooth,  it  should  be  sufficient 
to  accomplish  the  movements  as  rapidly  as  is  con¬ 
sistent  with  physiological  law.  When  pressure  is  once 


AND  HAND-BOOK. 


1 


67 


applied,  it  should  be  continued  without  relinquishment, 
for  there  should  be  no  retrogression  of  the  tooth. 

The  appliance  for  accomplishing  the  movement  of 
a  tooth  must  be  so  perfect  in  design,  construction,  ap¬ 
plication,  and  operation,  that  there  should  be  no 
need  for  its  removal  till  its  object  is  accomplished. 

RETAINING  APPLIANCES. 

After  the  mal-posed  tooth  has  been  moved  into 
the  desired  position  and  proper  occlusion  secured,  it 
should  be  firmly  supported  and  retained  till  it  has 
become  firm  in  its  new  socket.  “  The  importance  of 
a  steady  support  and  rest  while  the  tooth  is  becoming 
firm  is  well  illustrated,”  says  Guilford,  ‘‘  in  the 
necessity  of  placing  a  fractured  limb  in  immovable 
splints.” 

A  strip  of  32  to  36  gauge  platina,  about  i  of  an  inch 
wide,  is  made  into  a  loop  and  slipped  over  the  tooth  to 
be  banded.  The  ends  are  now  grasped  close  to  the 
tooth  with  a  pair  of  flat-nosed  pliers,  and  the  band 
drawn  tightly  round  the  tooth,  a  strong  burnisher 
being  applied  at  the  same  time  to  still  further  make  it 
conform  to  the  shape  of  the  tooth.  A  small  bit  of 
solder  is  now  placed  in  the  band  at  the  junction,  and 
all  carried  in  contact  with  the  flame  of  the  soldering 
lamp.  After  it  is  soldered  the  ends  are  chipped  off,  and 
the  band  is  now  complete  and  ready  for  any  attach¬ 
ments  which  may  be  made ;  after  which  it  is  cemented 
in  position  on  the  tooth. 


68 


student’s  manual 


For  accomplishing  the  dilFerent  movements  of  the 
teeth,  I  use  the  following  simple  appliances  : 

c 


Fig.  1.  shows  two  forms  of  the  screw  :  one  for  push¬ 
ing,  as  shown  at  1  ;  one  for  pulling,  as  shown  at  2  ; 
and  a  lever  for  rotating,  as  shown  at  3.  For  making 
and  using  these  appliances,  use  Stubb’s  steel  wire  of  two 
sizes.  You  will  also  need  jewelers’  gold-plated  wire  and 
hollow  wire,  or,  as  it  is  known  among  jewelers,  “joint 
wire,”  which  may  be  of  either  gold  or  silver,  and  a 
few  pieces  of  piano  wire.  The  screw  for  pushing  is 
made  by  cutting  a  thread  on  a  piece  of  Stubb’s  steel 
wire  of  the  desired  size  and  length.  One  end  of  this 
screw  is  beaten  flat,  and  to  the  other  end  is  screwed  a 
small  nut  made  of  platinized  gold.  This  complete  is 
shown  at  4.  A  piece  of  the  joint  wire  is  now  sawed 
off  the  desired  length.  The  screw  is  slipped  into  this 


AND  HAND-BOOK. 


69 


pipe,  find  the  whole  is  now  complete  and  ready  for  use, 
as  shown  at  1.  This  style  of  screw  may  be  made  any 
size  or  length  ;  the  largest  I  have  yet  made  being  22- 
inches  in  length,  the  shortest  f  inch. 

The  traction  screw  is  made  of  Stubb’s  steel  wire,  in 
a  similar  manner  to  the  screw  just  described,  with  the 
exception  that  one  end  of  the  screw  is  bent  sharply 
at  right  angles.  The  screw  complete  is  shown  at  2. 
The  entire  length  of  the  screw  is  about  I  of  an  inch, 
the  angle  or  bent  portion  3-32  of  an  inch. 

The  lever  is  made  of  a  piece  of  piano  wire  (No. 
13),  about  2i  inches  in  length,  bent  at  one  end  into 
the  form  of  an  eye.  It  is  shown  complete  at  3. 

Rotation  by  means  of  this  instrument  is  accom¬ 
plished  by  banding  the  tooth  to  be  rotated.  Before 
cementing  the  band  in  position  on  the  tooth,  a  piece 
of  joint  wire  i  inch  long  is  soldered  on  to  the  band 
on  the  labial  or  buccal  surface  at  right  angles  to  the 
axis  of  the  tooth.  The  band  is  now  cemented  in  posi¬ 
tion  on  the  tooth.  The  straight  end  of  the  piano  wire 
is  inserted  into  the  little  pipe  in  the  band.  The  other 
end  sprung  round  and  made  fast  by  a  wire  ligature  to 
the  tooth  nearest  the  eye  in  the  end  of  the  lever. 
Fig.  2.  shows  an  incisor  being  rotated  by  this  method. 

After  the  tooth  has  been  moved  into  position  it  is 
retained  by  removing  the  spring  and  inserting  a  piece 
of  the  gold  plated  wire  into  the  tube  from  the  oppo¬ 
site  side,  long  enough  for  the  end  to  rest  on  the  labial 


70 


student’s  manual 


Fig.  2. 


surface  of  the  tooth  adjoining,  as  shown  in  Fig.  3. 
The  piece  of  wire  is  pre¬ 
vented  from  turning  or 
working  out,  by  passing  a 
fine  drill  through  the  pipe 
and  one  side  of  the  wire, 

and  inserting  a  neatly-fitting  piece  in  the  hole  thus 
made. 

For  accomplishing  the  movements  of  a  tooth  from 
within  outward  into  the  line  of  the  arch,  the  screw 
first  described  is  used  in  the  following  manner  :  The 
tooth  to  be  moved  is  banded  and  piped  in  the  same 
manner  as  described  in  rotation  ;  then  into  the  pala- 


AND  HAND-BOOK. 


71 


tal  side  of  the  band  is  formed  a  slat,  into  which  is 
inserted  the  flat  end  of  the  screw.  Kesistance  is 
gained  for  the  base  of  the  screw  by  selecting  a  suffi¬ 
cient  number  of  teeth  to  completely  resist  the  pressure 
of  the  moving  tooth. 

These  teeth  are  banded  and  piped  close  to  the  gum, 
and  on  a  line  with  it.  A  piece  of  the  gold  plated 
wire  is  threaded  through  these  little  pipes,  either  be¬ 
fore  or  after  cementing  the  bands  in  position.  Against 
this  wire  is  placed  the  base  of  the  pipe  encircling  the 
screw.  A  suitable  notch  is  fitted  into  the  end  of  the 


Fig.  4. 

pipe,  to  fit  the  wire  and  prevent  it  from  slipping ;  or, 
if  this  wire  of  resistance  is  placed  on  the  outside  of 
the  arch,  as  may  be  done  with  advantage  in  many 


72 


student’s  manual 


cases,  the  base  of  the  pipe  is  rested  against  one  of  the 
bands  encireling  one  of  the  teeth.  It  is  prevented 
from  slipping  by  soldering  it  in  position,  or  by  plug¬ 
ging  the  end  of  the  pipe,  and  filing  it  to  a  sharp  point. 
The  point  rests  in  a  pit  formed  in  the  band.  Fig.  4 
shows  the  screw  in  position  in  moving  an  inlocked 
cuspid. 

Force  is  applied  by  tightening  the  nut  with  a  small 
wreneh  after  the  tooth  has  been  moved  into  the  line 
of  the  areh.  If  the  movement  of  rotation  is  necessary 
the  lever  is  applied,  after  which  it  is  retained  by  in¬ 
serting  a  piece  of  the  plated  wire  into  the  little  pipe. 
The  end  of  the  wire  resting  against  the  outer  surface 
of  the  tooth  on  each  side  is  shown  in  Fig.  5. 

The  movement  of  a  tooth  in¬ 
ward  into  the  line  of  the  arch  is 
accomplished  by  banding  the 
tooth.  To  the  palatal  side  of 
the  band,  close  to  and  on  a  line 
with  the  gum,  is  soldered  one  of  5- 

the  little  pipes  3^^  of  an  inch  long.  Into  this  pipe  is 
hooked  the  angle  of  the  traction  screw.  Resistance 
is  gained  by  banding  piping  on  one  or  more  teeth  on 
each  side  of  the  tooth  to  be  moved,  the  pipes  being 
soldered  close  to  and  on  a  line  with  the  gum. 
Through  these  little  pipes,  either  before  or  after 
cementing  in  position,  is  threaded  a  piece  of  the 
plated  wire. 


AND  HAND-BOOK’ 


73 


Pressure  is  now  exerted  by  the  screw  pulling 
through,  and  the  nut  working  against  the  end  of 
another  of  these  little  pipes  soldered  to  the  wire  of  re¬ 
sistance.  Fig.  6  shows  a  lateral  incisor  being  drawn 
into  line.  The  nut  is  tightened  as  often  as  necessary. 
The  end  of  the  screw  is  snipped  off  from  time  to  time 
to  prevent  its  chafing  the  tongue. 


Fig.  6. 

After  the  tooth  has  been  drawn  into  line,  the  wire 
of  resistance  and  the  traction  screw  are  removed,  and 
the  tooth  is  retained  in  position  by  inserting  a  piece 

of  the  j^lated  wire  into  the 
little  pipe  before  occupied  by 
the  angle  of  the  traction 
screw,  the  wire  being  long 
Fig.  7.  enough  for  the  ends  to  rest 


74 


student’s  manual 


against  the  palatal  surface  of  the  tooth  on  each  side, 
as  shown  in  Fig.  7.  The  retaining  wire  is  held  in 
position  as  shown  in  Fig.  3. 

The  movement  of  a  tooth  backward  in  a  line  of 
the  arch  is  accomplished  by  banding  the  tooth  to  be 
moved.  To  the  outward  surface  of  the  band  is 
soldered  one  of  the  pipes  of  an  inch  long,  at  right- 
angles  to  the  tooth,  and  line  of  the  arch.  Into  this 


Fig  8. 


pipe  is  hooked  the  angle  of  the  traction  screw.  The 
other  end  of  the  screw  passes  through,  and  the  nut 
works  against,  the  end  of  the  pipe  soldered  to  the 


AND  HAND-BOOK. 


75 


bands  encircling  the  teeth  to  be  used  in  overcoming 
the  resistance  of  the  tooth  being  moved.  Fig.  8  shows 
a  cuspid  being  drawn  backward.  It  will  be  seen  that 
the  movement,  tipping,  which  is  the  ideal,  is  thus 
gained,  and  though  the  pressure  is  exerted  on  one 
side  of  the  tooth  only,  yet  rotation  is  impossible,  as  it 
moves  backward.  It  will  also  be  seen  that  the  re¬ 
sistance  is  complete,  as  the  teeth  used  for  this  purpose 
cannot  tip,  but  must  be  dragged  forward  bodily 
through  the  alveolus.  The  screw  is  snipped  off  from  time 
to  time  as  it  emerges  through  the  pipe  and  chafes  the 
cheek,  or  the  cheek  may  be  protected  by  covering  the 
end  of  the  screw  with  a  piece  of  warmed  gutta¬ 
percha. 

After  the  tooth  has  been  moved  backward  the  de¬ 
sired  distance,  it  is  retained  there  by  the  screw  being 
kept  in  position,  or  it  may  be  removed  and  a  piece  of 
gold  Avire  inserted  in  its  place. 

The  movement  of  a  tooth  forward  in  line  of  the 
arch  is  accomplished  in  the  same  way,  only  selecting 
teeth  from  the  opposite  side  to  be  used  in  overcoming 
the  resistance  of  the  teeth  being  moved. 

The  expansion  of  the  arch  is  accomplished  by 
placing  a  bar  of  heaviest  piano  wire  against  the  palatal 
side  of  the  arch,  one  on  each  side.  They  are  held  in 
position  by  the  ends  in  front  23assing  through  little 
pipes  soldered  to  bands  encircling  the  cuspids.  The 
posterior  ends  are  kept  in  position  by  the  ends  of  the 


76 


student’s  manual 


wire  being  bent  sbarj^ly  at  right  angles,  and  hooked 
into  little  pipes  attached  to  bands  encircling  the  last 
molars. 

Thus  it  will  be  seen  that  two  rigid  bars  of  steel,  one 
on  each  side,  are  held  firmly  in  contact  with  the  teeth. 
As  shown  in  Fig.  10,  pressure  may  be  exerted  by 
placing  the  screw  first  described  directly  across  the 
arch.  The  opposite  ends  resting  against  the  bars  of 
steel ;  expansion  is  gained  by  tightening  the  nut  on 
the  screw. 

A  better  method  of  applying  pressure  against  these 
two  bars  is  to  bend  a  piece  of  heavy  steel-wire  to  con¬ 
form  to  the  curve  of  the  arch  across  from  bar  to 
bar.  At  the  side  near  one  end  is  filed  a  notch  fitting 
neatly  one  of  the  bars  which  it  is  to  rest  against. 
The  other  end  is  beaten  slightly  flat  and  a  hole 
drilled  through  at  a  point  directly  opposite  the  other 
bar  on  that  side  of  the  arch.  Through  this  hole  is 
placed  the  screw  for  pushing,  as  shown  in  Figs.  1  and 
4.  The  screw  should  not  be  over  1  of  an  inch  in 
length. 

This  appliance  is  now 
ready  to  place  in  posi¬ 
tion,  as  shown  in  Fig.  9. 
It  is  in  position  in  Figure 
10. 

Pressure  is  exerted  by 


Fig.  9 


AND  HAND-BOOK. 


77 


tightening  the  nut.  After  the  nut  has  traveled  the 
length  of  the  screw,  the  bent  wire  is  removed  and 
straightened  a  little  that  the  screw  may  have  more 
action.  It  will  be  seen  in  the  engraving  that  two  of 
these  screws  and  braces  are  used,  one  to  remain  in 
position  while  the  other  is  being  straightened,  thus 
preventing  the  teeth  from  moving  back,  as  would  be 
the  case  if  but  one  was  used. 

These  braces  are  moved  along  the  bars  forward  or 


Fig.  10. 

backward  according  as  pressure  is  needed.  After  the 
sides  of  the  arch  have  been  pressed  apart  the  desired 


78 


student’s  manual 


distance,  they  are  retained  by  a  straight  bar  passing 
across  the  arch  from  cuspid  to  cuspid,  the  ends  being 
bent  sharply  at  right  angles  and  hooked  into  little 
pipes,  soldered  at  right  angles  to  the  pipes  already 
described  as  attached  to  bands  encircling  cuspids. 

The  incisors  are  drawn  into  line  by  means  of  the 
lever  and  traction  screw,  this  cross-bar  serving  as  the 
wire  of  resistance  for  the  traction  screw  to  pull  to. 

This  method  of  expansion  may  be  aj^plied  to  the 
lower  arch  as  well,  as  little  interference  is  offered  to 


the  movement  of  the  tongue.  If  several  teeth  are  to 
be  retained  in  position,  one  molar  on  each  side  of  the 
arch  is  banded  and  pi2:)ed  on  a  line  parallel  with  their 


AND  HAND-BOOK. 


79 


axis.  Into  this  pipe  is  hooked  the  ends  of  a  piece  of 
the  plated  wire,  bent  to  conform  to  the  shape  of  the 
arch  and  snugly  encircling  it.  To  this  wire  is  at¬ 
tached  by  bands  and  pipes  such  teeth  as  should  be 
supported.  Fig.  11  shows  such  a  retaining  appliance. 

Such  is  the  general  method  of  using  these  three 
appliances,  but  the  different  ways  in  which  they  may 
be  applied  are  almost  innumerable,  each  case  requir¬ 
ing  some  slight  modification. 

The  greatest  care  and  accuracy  should  be  observed 
in  the  construction,  application  and  use  of  these  ap¬ 
pliances.  The  little  tube  should  be  of  gold  and  fit 
snugly  the  different  parts  of  the  appliances  passing 
through  them.  The  rubber  dam  should  always  be 
adjusted  about  the  teeth  before  fitting  and  cementing 
the  bands  into  position,  and  the  cement  used  should  be 
of  the  finest  quality.  The  screws  may  be  made  of 
platinized  gold,  or  if  of  steel  they  should  be  nickel- 
plated. 


t  1 


